Question

Simplifique as expressões:

a) (x + 1)² - (x - 2)² =

b) ( -x + 3)² - 2x(4 - x)

Me ajudem pf!

Answer 1

( x + 2)² - ( x - 1)²
( x² + 2.2.x + 2² ) -  ( x² - 2.1.x. + 1² ) =
( x² + 4x + 4 ) - ( x² - 2x + 1 ) =
x² + 4x + 4 - x² + 2x - 1 = 0
6x + 3 = 0
6x = -3
x = -3/6 = - 1/3 ****

b
( - x + 3 )² - 2x ( 4 - x) =
[ (-x)² + 2.(-x ). 3  + 3² )] - 8x + 2x² =
x² -6x + 9 - 8x + 2x²  =
3x² - 14x + 9 = 0