The value of y varies directly with x.If x=3, then y=21. Using the Direct Variation equation What is the value of x if y=105
To solve this problem using the Direct Variation equation, we can set up a proportion using the given information.
We are told that the value of y varies directly with x. This can be represented by the equation y = kx, where k is the constant of variation.
We know that when x = 3, y = 21. Using this information, we can solve for the value of k.
Plugging the values into the equation, we have 21 = k * 3. To find k, we divide both sides of the equation by 3: 21/3 = (k * 3)/3. Simplifying, we get 7 = k.
Now that we know the value of k is 7, we can use it to find the value of x when y = 105.
Using the direct variation equation y = kx, we can plug in the values: 105 = 7x. To solve for x, we divide both sides of the equation by 7: 105/7 = (7x)/7. Simplifying, we get 15 = x.
Therefore, when y = 105, the value of x is 15.
To find the value of x when y = 105, we can use the direct variation equation.
The direct variation equation is y = kx, where k is the constant of variation.
Given that when x = 3, y = 21, we can use these values to solve for k.
21 = k * 3
To find k, we divide both sides of the equation by 3:
k = 21 / 3
k = 7
Now we can use k to find the value of x when y = 105.
105 = 7x
To solve for x, we divide both sides of the equation by 7:
105 / 7 = x
15 = x
Therefore, when y = 105, x = 15.
y = kx
21 = k*3
Now use that to find x as needed.
Or, since y/x is constant (k), you can find the new x without even finding k.
You want x such that
105/x = 21/3