Question

When solving for the value of x in the equation 4(x - 1) + 3 = 18,

Aaron wrote the following lines on the board.
[line 1] 4(x - 1) + 3 = 18
[line 2] 4(x - 1) = 15
[line 3] 4x - 1 = 15
[line 4] 4x = 16
[line 5] x=4
Which property was used incorrectly when going from line 2 to line 3?
(1) distributive (3) associative
(2) commutative (4) multiplicative inverse

Answer 1

4(x - 1) + 3 = 18
4(x) - 4(1) + 3 = 18
4x - 4 + 3 = 18
4x - 1 = 18
+ 1 + 1
4x = 19
4 4
x = 4³/₄
The answer is line 3.

Answer 2

(1) distributive is the answer. Distributive property just means 4(x-1)=4x-4