25 ft
The triangles are proportional. There is the small triangle (5 ft, 6 ft, hypotenuse). There is the larger triangle that includes the small triangle (30 ft, height).
That means the side lengths are proportional.
5h=630+6→ The side lengths of the small triangle over the side lengths of the large triangle, with h representing the unknown height.
Now, let's solve the proportion:
5h=630→ Simplify the second fraction
5h=15→ Cross multiply (multiply the h by 1, the 5 by 6) and set the products equal to each other
h=5⋅5
h=25→ This is the height
