Answer:
x = 45/7
Step-by-step explanation:
[tex]\frac{5}{7} =\frac{x}{9}[/tex]
Here, you can more easily see what the fractions look like.
In order to cross-multiply, you have to multiply 5 with 9, and 7 with x.
45 = 7x
Then, you isolate x by dividing 7 on both sides:
45/7 = x
Hope I helped :)