.more kids homework... factoring?

Question

1. rewrite the middle term as the sum of two terms and then factor completely 15x^2 -21x +6

2. rewrite the middle term as the sum of two terms and then facto by grouping. x^2 - 14x +45

3. rerewrite the middle term as the sum of two terms and then facto by grouping x^2 + 19x +90

4. rewrite the middle term as the sum of two terms and then facto by grouping x^2 -2x -63

5.solve x^2 = -6x

ok almost done.. so far she shas been doing good :) my kids they are so much smarter than me

Answer 1

.more kids homework... factoring?
1. rewrite the middle term as the sum of two terms and then factor completely 15x^2 -21x +6

3(5x^2-7x+2)
3(5x^2-5x-2x+2)
3(5x-2)(x-1)

2. rewrite the middle term as the sum of two terms and then facto by grouping. x^2 - 14x +45

x^2-9x-5x+45
(x-9)(x-5)

3. rerewrite the middle term as the sum of two terms and then facto by grouping x^2 + 19x +90

x^2-10x+9x+90
(x+10)(x+9)

4. rewrite the middle term as the sum of two terms and then facto by grouping x^2 -2x -63

x^2-9x+7x-63
(x-9)(x+7)

5.solve x^2 = -6x

x=-6

Answer 2

1. First factor out the 3 and get 3(5x^2 -7x+2)
Now if you HAVE to rewrite the middle term, try -5x and -2x
3(5x-2)(x-1)

2. Theink of 2 numbers that multiply to give 45 and add to give
neg 14: -5 and -9 so it's -5x and -9x

(x-9)(x-5)

3. 10 x and 9x

(x+9)(x+10)

4. -9x and 7x

(x-9)(x+7)

5. add 6x to both sides

x^2 +6x=0

factor

x(x+6)=0

set each factor =0

x=0, or x+6=0 so x=-6

two solutions, 0, -6

I used to teach math and I would never teach factoring this way. When the problems get more difficult and the first term has a coefficient the kids think the 'trick' works, and it won't.


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Answer 3

i do consider you i'm a 14 year previous center college pupil. i'm taking Algebra a million that's a 9th grade math course. My instructor supplies us approximately 80 5 problems a night, now and lower back over one hundred. by skill of the time I end that and function eaten dinner and showered, its already approximately 10 oclock and that i ought to start making waiting for mattress and that i nonetheless have extra homework to do in different instructions. once I do have activities, I ought to make a call wherein homework im going to do and which im no longer, so i think of their must be a cut back. In my district. they say 10 min in line with grade. because of the fact that i'm in 8th grade, thats 80 min, a million hour and 20 min. i think of alot of instructors dont comprehend that we do produce different instructions and that they assume us do to 80 min of their artwork. So specific, there must be a strict cut back.

Answer 4

Well...perhaps you're a mum.

Let your kids do the practice. You aren't helping them by doing their work, but only deprive them the chance of building their own foundation in Mathematics. In math, ONLY Perfect Practice makes Perfect.

Answer 5

You can't be asking these questions here...
They are for your practice. Anyone here can probably solve them, but the whole purpose of giving you practice for these problems is killed.