System of equations:
w=(3/2)*h (1)
w*h=54 area (2)
w=54/h substitute into (1)
54/h=3h/2
3h²=54*2
h²= 36 (we take only positive solution)
h = √36=6
h=6 in.
w=(3/2)*h=(3/2)*6= 9
w=9 in.
correct answer is D
Answer:
the answers are
a) Area of triangle is 15 square inches
Perimeter of triangle is 18.5 inches.
b) Area of trapezium is 210 square cm.
Perimeter of trapezium is 61.5 cm.
c) Area of parallelogram is 21 square yards
perimeter of parallelogram is 22 yards
Step-by-step explanation:
Area of triangle is 1/2( base × height)
Area of trapezium is 1/2(p1 + p2)×height
Area of parallelogram is base × height
The rate of increase is found by differentiating with resepect to time. The product rule comes into play here.
A = LW
dA/dt ≈ (dL/dt)·W + L·(dW/dt)
... = (6 cm/s)·(5 cm) + (7 cm)·(3 cm/s)
... = 30 cm²/s + 21 cm²/s
... = 51 cm²/s . . . . rate of area increase