Question

Simplify the given expression.


(–3x2 – 9x + 17) – (15x2 + 20x – 4)

Answer 1

Answer:

$-18x^{2} -29x+13$

Step-by-step explanation:

We need to group terms according to the power of the variable x

So the math operation here is this:

$(-3-15)x^{2}+(-9-20)x+(17-4)\\-18x^{2} -29x+13$

Wich can not be simplified much longer

Answer 2

For this case we must simplify the following expression:

$(-3x ^ 2-9x + 17) - (15x ^ 2 + 20x-4) =$

We must bear in mind that by law of signs of multiplication it is fulfilled that:

$- * + = -\\- * - = +$

Then, rewriting:

$-3x ^ 2-9x + 17-15x ^ 2-20x + 4 =$

We add similar terms:

$-3x ^ 2-15x ^ 2-9x-20x + 17 + 4 =$

We have that equal signs are added and the same sign is placed, while different signs are subtracted and the sign of the major is placed, then:

$-18x ^ 2-29x + 21$

Answer:

$-18x ^ 2-29x + 21$