Simplify the following. (x²+2x)-(x²-7x)​

9x

Step-by-step explanation:

(x² + 2x) - (x² - 7x) ← distribute parenthesis

= x² + 2x - x² + 7x ← collect like terms

= 9x

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!