Simplify the given polynomial and use it to complete the statement (8x^2 -5x-7) - (9x^2-3x-5) + (x+7)(x+1)

Simplify the following: 8 x^2 - 5 x - 7 - (9 x^2 - 3 x - 5) + (x + 7) (x + 1)

-(9 x^2 - 3 x - 5) = -9 x^2 + 3 x + 5:

8 x^2 - 5 x - 7 + -9 x^2 + 3 x + 5 + (x + 7) (x + 1)

(x + 1) (x + 7) = (x) (x) + (x) (7) + (1) (x) + (1) (7) = x^2 + 7 x + x + 7 = x^2 + 8 x + 7:

x^2 + 8 x + 7 + 8 x^2 - 9 x^2 + 3 x - 5 x - 7 + 5

Grouping like terms, 8 x^2 + x^2 - 9 x^2 + 8 x + 3 x - 5 x - 7 + 5 + 7 = (-5 x + 3 x + 8 x) + (8 x^2 - 9 x^2 + x^2) + (-7 + 5 + 7):

(-5 x + 3 x + 8 x) + (8 x^2 - 9 x^2 + x^2) + (-7 + 5 + 7)

-5 x + 3 x + 8 x = 6 x:

6 x + (8 x^2 - 9 x^2 + x^2) + (-7 + 5 + 7)

-7 + 5 + 7 = 5:

6 x + (8 x^2 - 9 x^2 + x^2) + 5

8 x^2 + (x^2 - 9 x^2) = 0:

6 x + 5

d

step-by-step explanation:

i used the pitagoras theoreme