We know that the area A of a triangle is given by
[tex]A=\frac{1}{2}bh[/tex]where b is the base and h is the height.
Now in our case the area A = 15 in^2, h = 6 in, and b = x; therefore, the above equation gives
[tex]15=\frac{1}{2}\cdot6\cdot x[/tex]multiplying both sides by 2 gives
[tex]30=6x[/tex]Finally, dividing both sides by 6 gives
[tex]x=\frac{30}{6}[/tex][tex]x=5[/tex]Hence, x = 5 in, which is our answer!
