Question

7*. All lengths are in cm. Find the area of the right angled

triangle.
x-14( shortest side)
2x+5( hypotenuse)
2x+3( remaining side)

Answer 1

504 cm^2.

Explanation:

By Pythagoras:

(2x + 5)^2 = (2x + 3)^2 + (x - 14)^2

4x^2 + 20x + 25 = 4x^2 + 12x + 9 + x^2 - 28x + 196

20x - 12x + 28x + 25 - 9 - 196 = x^2

x^2 - 36x + 180 = 0

(x - 6)(x - 30) = 0

x = 6, 30.

As one of the sides is x - 14, x mst be 30 as its length has to be positive.

So the area of the triangle

= 1/2 * (x - 14) 8 (2x + 3)

= 1/2 * (30-14)(60 + 3)

= 1/2 * 16 * 63

= 504 cm^2.