Question

The base and the height of a triangle are in the ratio $4:5$. If the area of the triangle is $40m^2$, then the length of its base, is

Answer 1

Let base of the triangle $=4x$ and height $=5x$
Area of triangle $=\frac{1}{2}\times base\times height$
$40=\frac{1}{2}\times 4x\times 5x=>x^2=4$
$x=2$
Hence, base $=4x=8m$