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3 years ago

If q is directly proportional to (p-1)^2 and q=20 when p=3,find the values of p when q=80

Mathematics

1 answer:

Nastasia [14]3 years ago

7 0

Answer:

p = 17 and -15

Step-by-step explanation:

If q is directly proportional to (p-1)², this can be written as;

q = k(p-1)²

If q = 20 when p = 3

20 = k(3-1)²

20 = 2²k

20 = 4k

k = 5

To get p wen q = 80

80 = 5(p-1)²

16 = (p-1)²

p-1 = ±√16

p-1 = 16 and p-1 = -16

p = 17 and p=-16+1

p = 17 and -15

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If q is directly proportional to (p-1)^2 and q=20 when p=3,find the values of p when q=80​

If q is directly proportional to (p-1)^2 and q=20 when p=3,find the values of p when q=80