In direct variations, the formula is y=kx
In indirect variations, the formula is y=k/x
Where: y is a number, x is a number, and k is a constant
Examples:
1.Direct Variation
If y varies directly as x, and y = 8 when x = 12, find y when x=2.
a. Substitute the values to the formula to get the value of the constant.
y=kx
8=k(12)
k=8/12 or 2/3
b. We already got the constant, so we can now get the value of the missing y.
y=kx
y=(2/3)(2)
y=4/3 So, this is the answer.
2. Indirect Variation
If y varies indirectly as x, and y = 8 when x = 12, find y when x=2.
a. Substitute the values to the formula to get the value of the constant.
y=k/x
8=k/12
k=(2)(12)
k=24
b. We already got the constant, so we can now get the value of the missing y.
y=kx
y=24/2
y=12 So, this is the answer.
∞Indirect Variation is also called as Inverse Variation∞