Question

The base and the altitude of a triangle are $(3x-4y)$ and $(6x+5y)$ respectively. Find its area.

Answer 1

Given base and altitude of triangle are $(3x-4y)$ and $(6x+5y)$

We need to find area.

Therefore, area of triangle $=\frac{1}{2}\times \text{base}\times \text{altitude}$

$=\frac{1}{2}\times (3x-4y)\times (6x+5y)$

$=\frac{3x(6x+5y)-4y(6x+5y)}{2}$

$=\frac{18x^2+15xy-24xy-20y^2}{2}$

$=\frac{1}{2}(18x^2-9xy-20y^2)$

$=(9x^2-4.5xy-10y^2)$