Answer:
3x+21=57
Step-by-step explanation:
When we use distributive property we do
[tex]3*x[/tex] and [tex]3*7[/tex] which will like this when rewritten [tex]3x+21=57[/tex]
Check answer:
[tex]3x+21=57\\-21=-21\\3x=36[/tex] [tex]\frac{3x}{3} =\frac{36}{3}[/tex]
x=12 3(12)+21=57
36+21=57