Answer:
10.
Step-by-step explanation:
6/9 = x/15
9x = 6*15
9x = 90
x = 10.
10
[tex]\frac{6}{15} =\frac{x}{x+15}[/tex]
[tex]6(x+15)=15x[/tex]
[tex]6x+90=15x[/tex]
[tex]90=15-6x[/tex]
[tex]90=9x[/tex]
[tex]x=90/9= 10[/tex]
Hope this helps
