Question

The length of the base of the triangular sheet of canvas above the door of the tent in figure is $2$ feet more than twice its height. The area is $30$ square feet. Find the length of the base of triangle.

• A. $18$ feet
• B. $12$ feet
• C. $14$ feet
• D. $6$ feet

Answer 1

The correct option is B $12$ feet

Let length of base $=$ x
Given $x=2h+2$
Area $=\frac{1}{2}xth;\frac{1}{2}x\left(\frac{x-2}{2}\right)=30$
$\Rightarrow x^2-2x=120\Rightarrow x^2-(12-10)x-120=0$
$\Rightarrow x(x+10)-12(x+10)=0\Rightarrow x=12$