Kalyssa G. answered • 10/09/19

Experienced Computer Science and Math tutor

Because the shape is triangular, the area of a triangle is 1/2bh. If the area is 420 that means the dimensions is x multiplied by the height (5x-10)

But beacuse this is a triangle its .5x(5x-10)

When distributed its 2.5x^{2}-5x=420

if you use the quadratic formula youll get 2 roots

-12 and 14

since you cant have a negative length, x is 14. Leaving you with dimensions of 7 and 60