Answer:
Step-by-step explanation:
Diagram 1
Area = b*h/2 = 4y*(y+5)/2 = 2y*(y+5)= 2y² + 10y
Diagram 2
Area = side*side = y * y = y²
the area of the triangle exceeds the rectangle by 39 cm².
2y² + 10y - y² = 39
y² + 10y = 39
y² + 10y -39 = 0
y² +13y - 3y - 3*13 = 0
y(y+13) -3(y+13)=0
(y+13)(y-3) = 0
y + 13 = 0 will not come as length couldn't be in negative
y - 3 = 0
y = 3 cm
Diagram 2:
Perimeter = 4*side = 4*y = 4*3 = 12 cm
