Question

Marta solved an equation. Her work is shown below. equation: 2(x-4) + 2x=x+7 line 1: 2x −8+2x = x+7 line 2: line 3: line 4: line 5: 4x8=x+7 3x -8=7 3x = 15 x = 5 Which step in Marta's work is justified by the distributive property?

A from the equation to line 1
B from line 4 to line 5
C from line 2 to line 3
D from line 1 to line 2​

Answer 1

The correct answer is D: from line 1 to line 2.

Explanation:

In line 1, Marta distributes the coefficient 2 to both terms inside the parentheses (x-4), resulting in 2x - 8. This step is justified by the distributive property.

Line 2 is obtained by combining like terms. In this case, Marta combines the two terms 2x and 2x on the left side of the equation to get 4x.