7+x=15
x=8
x = -7
2
X=7
x = 27
-7 +2x = x + 8 2x - x = 7 + 8 x = 15
-1
7
x=2 1/7
8.5x + 8 = 1.3x + 15 7.2x = 7 x = 0.972222(repeating)
4x+7-3x = 15 4x-3x = 15-7 x = 8
Move the numerals to the right hand side: x = 15 - 7 - 2 ie x = 6
x = -7, y = 2 ⇒ 2x3 + 15y = 2 x (-7)3 + 15 x 2 = 2 x (-343) + 15 x 2 = -656