The perimeter of a rectangle whose length is 6 metre more than its breadth is 84 metre. What is the area of the triangle whose base is equal to the diagonal of the rectangle and height is equal to the length of the rectangle ?
1). 360 sq. metre
2). 380 sq. metre
3). 360 metre
4). 400 sq. metre
Let the base of rectangle be y , then its length will be = y+6
perimeter of triangle = 84
2(length + breadth) = 84
2(2y + 6) = 84
2y + 6 = 42
y = 18 m
length of rectangle = height of triangle = 18 + 6 = 24 m
Diagonal of rectangle = base of Triangle = $\sqrt{(24)^2 + (18)^2}$ = 30
Area of Triangle = $\frac{1}{2}\times30\times24$
Area of Triangle = 360 sq m