I need help simplifying this equation...?

Question

-4(-a+3b)-3(a-5b)

and

x(4+y)-2x(y+7)

Answer 1

First multiply:

(-4)*(-a)+(-4)*(3b)+(-3)*(a)+(-3)*(-5b...

4a-12b-3a+15b

Then add like terms

a-3b

Do the same for the second problem:

Multiply:

(x)*(4)+(x)*(y)+(-2x)*(y)+(-2x)(7)

4x + xy -2xy -14x

Add like terms:

-10x-xy

Answer 2

You must distribute the -4 and the -3 into the parenthesis that follows it.

-4(-a+3b)-3(a-5b)

(4a - 12b)(-3a + 15b)

Now we multiply the two by multiplying 4a with -3a AND 15b AS WELL AS multiplying -12b with -3a AND 15b.

-12a^2 + 60ab + 36ab + 180b^2

Add the terms.

-12a^2 + 96ab +180b^2

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The second one is the same deal.

But because we're multiplying with variables as the coefficient of the parenthesis, it would be simpler to multiply the variables together after multiplying the parentheses together.

x(4 + y) - 2x(y + 7)

x * -2x (4+y)(y + 7)

x * -2x (4y^2 + 11y + 28)

-2x^2 (4y^2 + 11y + 28)

-8x^2 y^2 - 22 x^2 y - 56x^2