Solve for a_3
a_{3}=\frac{4}{b}
b\neq 0
Solve for b
b=\frac{4}{a_{3}}
a_{3}\neq 0
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2a_{3}b=2\times 4
Multiply both sides by 4.
a_{3}b=4
Cancel out 2 on both sides.
ba_{3}=4
The equation is in standard form.
\frac{ba_{3}}{b}=\frac{4}{b}
Divide both sides by b.
a_{3}=\frac{4}{b}
Dividing by b undoes the multiplication by b.
2a_{3}b=2\times 4
Multiply both sides by 4.
a_{3}b=4
Cancel out 2 on both sides.
\frac{a_{3}b}{a_{3}}=\frac{4}{a_{3}}
Divide both sides by a_{3}.
b=\frac{4}{a_{3}}
Dividing by a_{3} undoes the multiplication by a_{3}.
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