How do you solve #5r - 9= 3+ 3r#?

1 Answer
Sep 4, 2017

#r = 6", see explanation for how to solve."#

Explanation:

#5r - 9 = 3 + 3r#

#5r= 9 + 3 + 3r#

#5r - 3r= 9 + 3#

#2r= 12#

#r= 12/2#

#color(blue)(r= 6#

#"We can now substitute " 3 " for " r " to prove our answer."#

#5 xx 6 - 9 = 3 + 3 xx 6#

#30 - 9 = 3 + 18#

#30 - 9 = 21#

#21 = 21#