Răspuns:
Explicație pas cu pas:
a) 3x + 7 = 3(x − 2) + x <=> 3x+7 = 3x-6+x =>
3x+7-3x+6-x = 0 => 13-x = 0 => x = 13
b) (2x − 1)² = (x − 1)² + (2 + x)(2 − x) + 4x² =>
4x²-4x+1 = x²-2x+1 +4 - x² + 4x² =>
-4x+2x = 4 => -2x = 4 => x = -2
e) (x+3)² - 2x² = (x-2)² - 4x² - 3
x²+6x+9 - 2x² = x²-4x+4 - 4x²-3 =>
x²-2x²-x²+4x²+6x+4x = -9+4-3 =>
2x²+10x = -8 => x²+5x+4 = 0 <=>
(x+4)(x+1) = 0 => x₁ = -4 ; x₂ = -1
#copaceibrainly