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anonymous
 one year ago
The value of y varies directly with x2, and y = 36 when x = 3.
What is the value of y when x = 5?
anonymous
 one year ago
The value of y varies directly with x2, and y = 36 when x = 3. What is the value of y when x = 5?

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Nnesha
 one year ago
Best ResponseYou've already chosen the best response.0what is the equation for direct variation ?

radar
 one year ago
Best ResponseYou've already chosen the best response.2A direct variation means (when using y and x for the variable labels) When x increases so does y and vice versa, when x decreases so does y. For the given problem it would appears as:\[y= kx ^{2}. \]First step is to solve for k from the info given.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so the equation would be like 36=k3^2? or 36=k5^2

radar
 one year ago
Best ResponseYou've already chosen the best response.2Your are on the right track, from what is given 36 = k x^2, to solve for k substitute the value given for x. The value was (according to the problem) a 3 Sooo k 3^2 = 36 or 9k = 36 or k=36/9 k=??

radar
 one year ago
Best ResponseYou've already chosen the best response.2That value of k will remain the same for all values of x, so it is important to get the correct value. k is called the "constant of proportionally"

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so if you do k=36/9 k would equal 4?

radar
 one year ago
Best ResponseYou've already chosen the best response.2Yes k=4 so now you can proceed with the new value of x which is given as 5, use k and plug in the value of 5 for x, and don't forget it is x^2 which is used to solve for y.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0what would the equation look like again?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so y=4 5^2 or i keep the 36 in the y place

radar
 one year ago
Best ResponseYou've already chosen the best response.2No, ditch the 36 that was when x = 3. This is a new situation (except for k) when x = 5.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i got 100 as my answer cause 5^2 is 25 and 4 * 25 is 100

radar
 one year ago
Best ResponseYou've already chosen the best response.2Great, sorry with the slow response, I had visitors. You are correct.

radar
 one year ago
Best ResponseYou've already chosen the best response.2As always, good luck with your studies.
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