Download Direct Variation

Direct Variation
k=y
x
Example
and
(4,6) (8, 12) (2, 3)
y = kx
or
x
4
8
2
y
6
12
3
STEP 1
Place the y value over the x to make a fraction
y
x
6
4
12
8
3
2
STEP 2
Simplify the fraction – this is your constant k
6/4 = 3/2 12/8 = 3/2
3= k
2
NOTE – if your fractions are not all the same, then it is NOT a direct variation.
STEP 3
Put your k into the equation y=kx
DIRECT VARIATIONS
Must be straight and go through the origin.
As x increases, y increases
As x decreases, y decreases
y=3 x
2