How do you combine like terms in -5( 7+ 8x ) + x ( 3x - 5)?

2 Answers
Oct 18, 2017

The simplified answer is 3x^2+45x-35

Explanation:

1) Distribute -5 to (7+8x)
Distribute x to (3x-5)
This makes the equation (-35-40x)+(3x^2-5x)

2) Combine like terms
(-35-45x+3x^2)

3) Reword it so the squared 3x is first, then -45x, and finally -35

Final Answer

3x^2-45x-35

Oct 18, 2017

3x^2-45x-35
(see below for method)

Explanation:

underbrace(-5(7+8x))+underbrace(x(3x-5))

=-35-40xcolor(white)("xx")+color(white)("xx")3x^2-5x

Combining like terms:
{: (,"terms involving "x^2,color(white)("xx"),"terms involving "x,color(white)("xx"),"terms involving only constants"), (,3x^2,,-40x,,-35), (,ul(color(white)("XXXX")),,ul(-5x),,ul(color(white)("XXXX"))), (=color(white)("xx"),color(blue)(3x^2),,color(blue)(-45x),,color(blue)(-35)) :}