we know that area of the figure=area of triangle+area of rectangle area of the figure=90 ft²
step 1 find the area of triangle [tex]A=b*h/2[/tex] b=x h=x so [tex]A=(x*x)/2[/tex] Area of triangle=x²/2 ft²
step 2 find the area of rectangle [tex]A=b*h[/tex] b=2x h=x [tex]A=(2x)*x------\ \textgreater \ A=2x^{2} [/tex] area rectangle=2x²
step 3 find value of x area of the figure=(x²/2)+2x² area of the figure=90 ft² 90=(x²/2)+2x²-----> multiply by 2 both sides----> 180=x²+4x² 5x²=180-----> x²=36-----> x=6 ft
