Suppose that y varies directly with x and y=6 when x=15
find y when x=20
To find the value of y when x=20, we first need to determine the constant of variation (k) using the given values y=6 and x=15.
The direct variation formula is y = kx, where k is the constant of variation.
We can substitute the given values y=6 and x=15 into the formula to solve for k:
6 = k(15)
Divide both sides by 15 to solve for k:
k = 6/15
k = 0.4
Now that we have found the constant of variation, we can use this value to find y when x=20:
y = 0.4(20)
y = 8
Therefore, y=8 when x=20.