36/b - 4 =0 What is b ?
\(\dfrac{36}{b}-4=0\ \ \ \ |add\ 4\ to\ both\ sides\\\\\dfrac{36}{b}=4\\\\\dfrac{36}{b}=\dfrac{4}{1}\ \ \ \ |cross\ multiply\\\\4b=36\ \ \ \ |divide\ both\ sides\ by\ 4\\\\\boxed{b=9}\)
