Answer:
y = x / 7
Step-by-step explanation:
For us to get direct variation equation, we must introduce a constant term.
If y varies directly as x:
y ~ x
y = Kx
Where K, is the introduced constant.
Now let's solve to get a direct variation equation.
When y=3 , x=21
We substitute, y=3 and x=21 in the
y = Kx
3 = K 21
Divide both sides by 21
3 / 21 = K 21/ 21
K = 3/21
K = 1 / 7
Therefore, we introduce K = 1 / 7 into the mother equation.
y = 1/7 * x
y = x / 7
The direct variation equation for the situation:
y = x / 7