Question

If area of a triangular piece of cardboard is $90c{m}^2,$ then the length of altitude corresponding to $20cm$long base is ____ $cm.$

Answer 1

Solve for length of the altitude:

Given,

1. Area of a triangular piece of cardboard is $90c{m}^2,$
2. Length of the base is $20cm$

Area of triangle $=\frac{1}{2}\times$ base $\times$ height

$\Rightarrow$ $90=\frac{1}{2}\times 20\times$ height

$\Rightarrow$ Height $=\frac{2\times 90}{20}=9cm.$

Hence the length of the altitude is $9cm.$