Question

How tall is the lighthouse?

Answer 1

≈200ft

Explanation:

first the small triangle is measured

9²+15²=y²

y²=306

y=√306

y≈17.5

now bc the two triangles are similar, just different in sizes, this is done

17.5/9=z/120

z=(17.5*120)/9

z≈233.3

now the x is calculated

x²=233.3²-120²

x²=40028.89

x≈200