Question

C is directly proportional to the square of D and when C=32, D= 4. Find C when D= 3

Answer 1

Answer:C=6

Step-by-step explanation:C directly proportional to D

C=kD where k=constant

C=32, D=4×4

32=k16

K=32÷16

K=2

Now D=3 and k=2

C=kD

C=2×3

C=6

Answer 2

Answer: c=18

Explanation:

C is directly proportional to square of D

C € D2

€ rep directly proportional

C=kd2

K is a constant

C=32

D=4

Substitute

32=k(4^2)

32=k(16)

32=16k

K=32/16

K=2

Since we know our constant k to be 2

Substitute

We are looking for c,when d=3

C=kd2

C=2×(3^2)

C=2×9

C=18