Question

8x^3+4x^2-32x=112
can smeone plz show me how to solve this

Answer 1

8x³ + 4x² - 32x -112 = 0

4( 2x³ + x² - 8x - 28) = 0

2x³ + x² - 8x -28 = 0

Now we have to factor this

Answer 2

Do you know how to do it?

Answer 3

the original problem was (5/x+2)-(3/x+2)=12/x^2-4,
I followed the original steps you showed me, but I think I did something wrong

Answer 4

I am stuck at ((3(x+2)+5(x+2)/(x+2)(x+2))=3x+6+5x+10/x^2+4=8x+16/x^2+4=12/x^2-4

now what's next?

Answer 5

so the original problem had the same denominator for both fractions on the LHS. ( x+2)

So you just subtract.

(5-3) / (x + 2) = 12 / (x² -4)

2 / (x+2) = 12 / (x² -4)

now on the RHS the denominator you have to factor it.

it is of the form (a² - b² ). So the factors will be (a + b ) ( a-b)

so here our factors will be ( x +2 ) and (x-2)

2/(x+2) = 12 / [(x+2)(x-2)]

Now you multiply both sides by (x+2) since you have that factor in the denominator on both sides.

2 = 12 / (x-2)
now cross multiply

2 (x-2) = 12
2x -4 = 12
2x = 16
x = 8

Answer 6

with these type problems you may not encounter same steps.

Answer 7

you have to remember basic rules

Answer 8

1. Factor quadratic functions if any and cancel out common factors.
2. combine fractions after taking LCD.
3. Cross multiply fractions on either sides.
4.Simplify terms by combining like terms.

Answer 9

@aprilsages

Answer 10

got it sorry I was just reading all of it

Answer 11

ok got it thanks so much!

Answer 12

the first mistake you did was doing (x+2) (x+2) for LCD. both denominators are same. So you don't have to do that

Answer 13

yeah I found that out once u told me, I was sorta skeptical about it in the first place, it felt wrong

Answer 14

It is not required for this problem but still I noticed something in your work which is not right

(x +2 ) (x +2 ) is not x² + 4

Answer 15

ooooooo

Answer 16

k got it!