Answer:
15u = 135
Divide both sides by 15
u = 135/15 = 9
U is equal to 9
Hope this helps!
[tex]15 \times 4 = 135 \\ divide \: both \: sides \: of \: equcation \\ by \: 15 \\ \frac{15u}{15} = \frac{135}{15} \\ u = \frac{135}{15} \\ u = 9[/tex]