If the value of Y varies directly with x and y=-51 when x=3 find y if x=2

Answer 1

Since y varies directly with x, we know that a multiplier of k will be multiplied by x.

y = kx

In order to use this equation we need to know the value of k. That is why they gave us known values of x & y.

"when y = –51, x = 3"

Plug these values into our equation and solve for k.

–51 = k(3)

–51/3 = k Divide both sides by 3

k = –17 Simplify

Now that we know k our equation from here on is:

y = –17x

Now we can use this equation to solve y if x = 2 by plugging in 2 for x.

y = –17(2)

y = –34 FINAL ANSWER

Hope this helps!

Answer 2

If the value of Y varies directly with x and y=-51 when x=3 find y if x=2

Y varying directly with x suggests a function of the form Y = kx.

If Y was varying indirectly with x, a function would be suggested of the form Y = k / x.

Y = kx

Y(x) = Y(3) = -51

-51 = k*(3)

k = -51/3

k = -17

so the function is Y = -17*x

Y = -17x is used to solve for Y(x) = Y(2).

Y = -17 * 2

Y = -34

Y(2) = -34 is the answer that you seek.

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Answer 3

The words y Varies Directly with x should bring a certain equation to mind:

y = k x

where k is some constant that we need to figure out.

Now that we know the general formula, we plug in y and x to find k:

-51 = k (3)

divide both sides by 3

-17 = k

Now that we know k, we know the formula is

y = -17x

The last step is to find y when x = 2

So we simply plug in 2 for x:

y = -17 (2)

y = -34

Answer 4

You could view the question as a ratio of x:y, so that x:y = (3):(-51).

Given this, we can then solve for the ratio of x:y when x=1. This done by dividing the ratio in the question by 3 on both sides of the ratio to get x:y = (1):(-17).

The final step would be to figure out the ratio when x=2. This could be solved by multiplying the second ratio by two on both sides, to get x:y = (2) : (-34).

Therefore, when x=2, y would equal -34.

Hope this helps!