Answer:
x = 12.6
Step-by-step explanation:
When you have one fraction equated to another one, the means-extremes property allows you to cross multiply, as follows:
[tex]\frac{a}{b} = \frac{c}{d} [/tex]
can be rewritten as:
a*d = c*b
For this case:
[tex]\frac{5}{7} = \frac{9}{x} [/tex]
5*x = 7*9
x = 63/5
x = 12.6