Question

Lindsey, Laurie, and Mike showed their work solving the equation -3.3 + 73 - 5 = 8. Identify the student with the

invalid first step and (justify your reasoning)
Laurie - 3x + 7x - 5 = 8
-3x + 7x - 5 = 8
Lindsey -3x + 7x – 5 = 8
-3x + 7x = 13
mike -3x + 2x = 8
4x - 5 = 8

Answer 1

Laurie made an invalid first step by substituting variables instead of using the given numbers in the equation.

Step-by-step explanation:

The student with the invalid first step is Laurie. Laurie's first step is -3x + 7x - 5 = 8. The correct first step should be -3.3 + 73 - 5 = 8. Laurie made the mistake of substituting variables (x) instead of using the given numbers (-3.3, 73, and -5) in the equation.