Question

小华在解关于x的方程5a-x=13+2x时,误将-x看作+x,得到方程的解为x=-3,则原方程

Answer 1

5a + x = 13 + 2x

把 x = - 3 代入得：

5a - 3 = 13 - 6

5a = 10

a = 2

把 a = 2 代入 5a - x = 13 + 2x 得:

10 - x = 13 + 2x

2x + x = 10 - 13

3x = -3

x = (-3)÷3

x = -1