Question

find r

3(r - 7 ) = 4(2 - 2r) + 4

Answer 1

$\bf 3(r-7)=4(2-2r)+4\implies \stackrel{\textit{distributing}}{3r-21=8-8r+4}\implies 3r-21=12-8r \\\\\\ 11r-21=12\implies 11r=33\implies r=\cfrac{33}{11}\implies r=3$