1) 2(a+6)² - 9 = 63
2(a+6)² = 72
(a+6)² = 36
a²+12a +36 -36= 0
a²+12a = 0
a(a+12) = 0
a=0 ; a=-12
2) (2x-3)² = 1
4x² -12x +9 =1
4x² -12x +9 -1 = 0
4x² -12x +8 = 0
4(x² -3x +2) = 0
x² -3x +2 = 0
(x-2) (x-1) = 0
x=2 ; x=1
3) 6x² - 24x = 0
6x(x-4) = 0
x=0 ; x=4
4) 4m²+13m = 0
m(4m +13) = 0
m=0 ; m=-13/4
5) (2c + 1) (3c - 2) = 55
6c² -c -2 = 55
6c² -c -2 -55 = 0
6c² -c -57 = 0
(6c -19) (c+3) = 0
c=19/6 ; c=-3
