(b) 95 = (x+7)*(x-7) Expand the brackets: 95 = x² -7x + 7x -49 = x² - 49 Subtract x² from both sides: 95-x² = -49 Subtract 95 from both sides: -x²=-49-95 -x²= -144 Divide both sides by -1 to get rid of the negative numbers: -x²/-1=-144/-1 x²=144 Take the square root of 144: x = ± squareroot of 144 x = 12 or -12 x = 12 because you cannot have a negative age so Trina is 12 years old.