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3 years ago

If f(x) varies directly with x2, and f(x) = 40 when x = 2, find the value of f(5).

Mathematics

1 answer:

Paraphin [41]3 years ago

7 0

Answer:

C.250

Step-by-step explanation:

If f(x) varies directly with x^2

f(x) = k * x^2

f(x) = 40 when x=2. Substitute these values in

40 = k(2)^2

40 = k*4

Divide by 4

40/4 = 4k/4

10 =k

f(x) = 10x^2

Now we want to find f(x) when x=5. Substituting

f(5) = 10 *5^2

f(5) = 10 *25

f(5) = 250

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