Question

Calculati : a) 5 (x-3)-2(x+2)=2x-7 b) 2 (x-1)la puterea a 2.a = 72

Answer 1

a) 5x-15-(2x+4)=2x-7
5x-15-2x-4=2x-7
3x-19=2x-7
3x-2x=7+19
x=26

b)$2(x-1)^{2} =72$
2($x^{2}$-2x+1)=72
2$x^{2}$-4x+2=72
$2 x^{2} -4x-70=0$
Δ(delta)=$(-4)^{2} -4*2*(-70)$

Answer 2

a)5x-15-2x-4=2x-7
5x-2x-2x=-7+15+4
x=12
b)(2x-2)²=4x²-6x+4