Answer:
[tex]x=15[/tex]
Step-by-step explanation:
we have
[tex]\frac{5}{7}=\frac{x}{21}[/tex]
solve for x
That means ---> isolate the variable x
Multiply in cross
[tex]5(21)=x(7)[/tex]
[tex]105=7x[/tex]
Divide by 7 both sides
[tex]105/7=7x/7[/tex]
[tex]15=x[/tex]
Rewrite
[tex]x=15[/tex]
