Step-by-step explanation:
Area of triangle (A1)
= 1/2 * b *h
= 1/2 * 1 * 1
= 1/2 ft
Area of rectangle (A2)
= L * b
= 3 *1
= 3 ft
Total area
= A1 + A2
= 1/2 + 3
= (1 + 6 ) / 2
= 7/2 ft²
= 3.5 ft²
Hope it will help :)
