Question

a)2·[15-4(3x-8)]-7=3·[18-5(2x-3)]+18

b)(x+1)²-3(x+7)=3+(x-2)²

c)(x+2)(x-2)+4(x+3)=(x+2)²-3x

Answer 1

A) 2·[15-4(3x-8)]-7=3·[18-5(2x-3)]+18
     2 ( 47 - 12x) - 7 = 3.(33 - 10x )+ 18;
    94 - 24x - 7 = 99 - 30x + 18;
    6x = 30;
    x = 5;

B) (x+1)²-3(x+7)=3+(x-2)²;
     x² + 2x + 1 - 3x - 21 = 3 + x² - 4x + 4;
     3x = 27;
     x = 9;

C) (x+2)(x-2)+4(x+3)=(x+2)²-3x;
      x² - 4 + 4x + 12 = x²+ 4x + 4 - 3x;
     3x = - 4;
      x = - 4/3.