Since the area of a triangle is in the form area=0.5(base)(height) height=base+7 let base=x area=0.5(x)(7+x) 30=3.5x+0.5x^2 multiply the equation by 2 60=7x+x^2 subtract 60 from both sides x^2+7x-60=0 (x-5)(x+12)=0 thus x=5 or x=-12 since we are only considering positive answers x=-12 is rejected so base=5 and height=5+7=12