15x2-56 = 88+6x2 15x2-6x2-56-88 = 0 9x2-144 = 0 Divide all terms by 9:- x2-16 = 0 (x-4)(x+4) = 0 x = 4 or x = -4
If: 15x2-56 = 88+6x2 Then: 9x2 = 144 And: x2 = 16 So: x = 4
10x2 - 56 = 88 - 6x2 : 10x2 + 6x2 = 88 + 56 : 16x2 = 144 : x2 = 9 : x = ± 3
15x2 + 2x - 56 = 15x2 + 30x - 28x - 56 = 15x(x + 2) - 28(x + 2) = (15x - 28)(x + 2)
112
56
1 + 2 + 56 = 59
56 plus 1 equals 57. == ==
65
121
90
The answer is -56