when solving the equation 4(3x+2)-9=8x+7, Emily wrote 4 (3x+2)=8x+16 as her first step. which property justifies Emily first step?
1)commutative property of addition
2)addition property of equality
3)multiplication property of equality
4)distributive property of multiplication over addition
1)commutative property of addition
2)addition property of equality
3)multiplication property of equality
4)distributive property of multiplication over addition