Question

For which of the following equations is x = 7 not a solution?

4= -x + 11
-3x = x - 28
-5 = 2x – 9
5x = 2x + 21

Answer 1

Explanation:

Put x to the equation.

4=-7+11 => 4=4 ✓

-3•7=7-28 =>-21=-21 ✓

-5•7= 2•7-9 =>-35=5 is incorrect.

5•7=2•7+21 =>35=35 ✓

Hence,for the third equation x is not a solution.

Answer 2

Answer: For following equation x = 7 not a solution:

-5 = 2x-9