If we take both sides of the equation [tex] \frac{1}{3} x=5 [/tex] and multiply either expression by 3, the equality becomes
[tex] 3\cdot\frac{1}{3}x=3\cdot5\\x=15 [/tex]
Multiplication of both sides of an equality by the same number keeps the equality true, and we call this property the multiplication property of equality.