Algebra: How do YOU solve for 10x^2+x-21=0?

Someone I know IRL recently wrote, “I didn’t use algebra at all today.” That was probably not true, but no matter.

The Daughter is studying algebra right now in 8th grade and it’s a real PITA. Because she was so good in 7th grade math, she skipped over 8th grade math, what that was, and is now taking the math for 9th grade. This is a problem because she doesn’t know, and I surely don’t remember, what she’s missing.

I should note that when I was in 9th grade, I was very good in algebra. I remember helping a fellow student, Sid, at the chalkboard, when Miss McNulty couldn’t get him to understand.

I got a 97 in the Regents final. (Yes, I remember this; no I didn’t look it up. I got 86 in geometry and 98 is trigonometry.) But that was a HALF CENTURY AGO. THAT will make you feel old.

I have been depending on something called Tiger Algebra to help her muddle through.

For the problem 10x^2+x-21=0, where the ^ over the 6 key represents “power of,” so ten X squared in this case.

The factoring is the tough part to explain.

Factoring 10x^2+x-21
The first term is 10x^2 – its coefficient is 10
The middle term is +x its coefficient is 1
The last term, “the constant”, is -21

Step-1 : Multiply the coefficient of the first term by the constant 10 • -21 = -210

Step-2 : Find two factors of -210 whose sum equals the coefficient of the middle term, which is 1 .

-210 + 1 = -209
-105 + 2 = -103
-70 + 3 = -67
-42 + 5 = -37
-35 + 6 = -29
-30 + 7 = -23
-21 + 10 = -11
-15 + 14 = -1
-14 + 15 = 1 That’s it

By “it,” we’re talking the very beginning of “it.”

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -14 and 15
10x^2 – 14x + 15x – 21

Step-4 : Add up the first 2 terms, pulling out like factors :
2x • (5x-7)
Add up the last 2 terms, pulling out common factors :
3 • (5x-7)

Step-5 : Add up the four terms of step 4 :
(2x+3) • (5x-7)
Which is the desired factorization

At which point you take 2x+3=0 and 5x-7=0, and get 1.5 and 1.4 respectively, then do a whole bunch of other stuff with graphing designed to make your eyes glaze over.

We usually work on this in the morning, after the Daughter has felt despair the night before, which means doing it in lieu of me blogging in the morning, which is my best time for writing.

And she SORT OF understands parts of this. Hey, if you have an easier way to find the factors, please let me know. My blog will thank you, publicly if you want.

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The Lydster: when your heroes have feet of clay

Our family has developed a ritual of turning on CBS News This Morning to watch the 7 a.m. “eye-opener.” The morning of Tuesday, November 21, the Daughter noticed that Charlie Rose, co-anchor of the program wasn’t on, which wasn’t that odd.

What WAS unusual was the fact that in that segment of “your world in 90 seconds,” Charlie Rose DID appear. He had been suspended by CBS News the night before over sexual misconduct, as reported in the Washington Post, part of a string of men caught up recently. A reporter laid out the case, and then the other co-hosts, Norah O’Donnell and Gayle King, forcefully showed their disdain and shock.

And while she hadn’t said anything at the time, I could see the Daughter was confused and disappointed. I’ll admit I was, and that went for my wife as well. What I didn’t know at the time was that, a couple years prior, she’d written some report for school about the now-75-year-old anchor and contributor on 60 Minutes.

It’s that weird thing about how you begin to feel about people when you metaphorically let them into your home. You get a sense that you know a person. Heck, Norah and especially Gayle had expressed shock at the allegations, and they worked with the man for five years.

The initial allegations concerned his show put together by his production company, and airing on PBS and Bloomburg, prior to 2011. By the time he was fired, less than a day later, the accusations also included more recent events, including at CBS.

Of course, you DON’T know the people you see on TV or listen to on the radio. What I thought that knew about O.J. Simpson and especially Bill Cosby made their falls from grace much more difficult to comprehend.

We all discover that our heroes sometimes have feet of clay, and that’s an uncomfortable part of the learning process. It sucks, no matter at what age it happens.

The Lydster: Don’t learn this from daddy

As a followup to a question I answered in this blog months ago, someone, probably Chris, asked: Is there anything you don’t want her to learn from you? – the “her”, of course, being the Daughter.

I sent myself an email to remind me to write about it, but it got buried in other messages. As for the answer:

I don’t want her to find her sad place, or at least not to stay there for too long. I don’t want her to let the bastards keep her down.

I don’t want her to use food as a drug.

I don’t want her to be too proud or stubborn to ask for help.

I want her to be more tidy, not because it matters so much to me, but because it’ll matter to people she’ll encounter – roommates, friends and romantic entanglements.

I want her to drive a car with confidence and competence.

I want her to try to avoid senioritis, which I surely had in both high school and college.

I think I want her to find out what she wants to do in life sooner, but I’m not sure. The journey can have value in and of itself. AND work in the 21st century continues to be so different, she’ll probably have several jobs anyway.

I want her to travel much more than I have.

I want her to start saving for retirement earlier than I did.

I hope she can find a faith community that she is comfortable with in her twenties.

i’m sure there’s more, but that’s enough. That question is tough because, ultimately, it’s a dissection of myself as much as anything, and it’s a bit brutalizing, to tell the truth.

But as I’ve noted before, she does already have, for good or ill, a lot of my sensibilities. This parenting thing is every bit as difficult as I thought it’d be.

The Lydster: more empathetic

There was a Washington Post article in April 2017, The simple idea to make kids more empathetic? Get them reading the news. It’s about a specific program sythesizing the news.

One of the things I tried to protect the Daughter from was the news. I thought I was watching it when she was busy doing other things. But at some point, when she was eight or nine, I noticed she was picking up on stories. Moreover, she was aware of them at a level that I knew that her classmates were not. And that is still true.

I must admit this is a curse she has inherited from from her father, who was reading op/ed columns in the local paper at 9 or 10. William F. Buckley and Jack Anderson and the like was on my reading diet.

Following the news, she became more aware of the candidates for President – she hated Chris Christie, loved Bernie Sanders – and more of them than 90% of American adults.

I tried very hard not to inculcate her with my pain about race in America. Yet the evidence in the news, with only some minor clarification from me, really informed how she saw unarmed black men getting shot. I really didn’t want her to have to know about this, but it’s out there.

She has participated in walks to fight hunger. She has contributed money to help shelter animals. She really does have a good heart, which would probably embarrass her, but so be it.

I think that she will be a good citizen. She’ll follow the issues and she’ll always vote. At this point, I can’t see her ever running for office – at some level, she is very shy – but i can imagine her working behind the scenes for a candidate she supports. And perhaps she’ll surprise me.

The Lydster, Part 129: I Don’t Like Reggae

dreadlockholidayThis will surely shock some of you, but one day, I was singing a tune while sitting at the computer that just popped into my head. I couldn’t even really remember it, except for a chorus: “I don’t like reggae (oh, no), I love it (ooo yeah.)” Don’t own the recording, couldn’t even remember who performed it, and I may have misremembered the lyrics.

As it turns out, the song was called Continue reading

The Lydster, Part 128: Weird Al

weirdalThe Daughter was introduced to Weird Al Yankovic on the release of his July 2014 album, Mandatory Fun, which opened at #1 on the Billboard charts, the first comedy album since 1963 to top the charts. She went away for about a week to Grandma and Grandpa’s house in mid-August, spending time with her 13 y.o. twin cousins, and she comes home a Weird Al maven.

This is not a bad thing, mind you. I’ve been following the musician’s career for about three and a half decades, back when it was primarily him playing the accordion on songs such as My Bologna (parody of the Knack’s My Sharona) and Another One Rides the Bus (take on Queen’s Another One Bites the Dust) Continue reading

The Lydster, Part 127: Watching the news

NEWSFor her first nine years, I sheltered the Daughter from watching the evening news, viewing it after she went to bed, or before she got up in the morning. Sometimes, I’d watch it while she was in the other room.

Turns out that she is preternaturally interested in these things. Moreover, she develops opinions about them that did not necessarily come from us. Ferguson, MO made her aware that it’s a little scarier being a black child in America than she previously thought. The death of Palestinian children during the conflict with Israel made her angry. And she has great antipathy for Russia’s Putin.

Sometimes, she shows off her knowledge. Continue reading

The yard sale

yardsaleLet me state that I generally hate yard sales, garage sales, and the like. Specifically:
*I don’t like going to other people’s sales, especially when they put out things that are, to quote Oscar the Grouch, everything “ragged and rotten and rusty.”
*I don’t like having our own sale, because it involved going through lots of our own stuff. It’s time-consuming and enervating.
And most of all:
*I HATE bringing back into the house the stuff we decided to sell, but it didn’t.

Yet we (OK, the Wife and the Daughter) agreed (and I accepted the decision) to have a yard sale on September 6. The logic of that date was that it would be after school began, but before the fall got going in earnest. Continue reading

The 9/11 Memorial

Memorial-PoolAfter 9/11/2001, I had only been in Manhattan once that wasn’t in passing (train station to Charlotte, e.g.) and that was seeing a musical in 2003. I had never been particularly close geographically to Ground Zero, despite living less than 160 miles away.

When Rebecca (niece #1), her husband Rico, and a couple of their friends came out from California to NYC around Thanksgiving 2013, one of them items on the Californians’ agenda was to see the 9/11 memorial.

The museum exterior was at the site, but not yet open. Continue reading