By rewriting the equation from step 1 substituting the value of k into it, the value of x is 22.5
A direct variation is a type of variation that has two types of variables in which a variable can be expressed in terms of the other with its constant.
For example;
If x varies directly as y
<h3>Step 1:</h3>Then
- x
y
- x = ky ; where k is constant
The original question says:
- if x varies directly as y, and x = 9 when y = 6, find x when y = 15
∴
x = ky
9 = k × (6)
k = 9/6
k = 1.5
<h3>Step 3:</h3>Now, we can rewrite the equation from step 1 substituting the value of k into it:
∴
x = ky
- when y = 15 and k = 1.5
The value of (x) will be:
x = 1.5 (15)
x = 22.5
Learn more about Direct variation here: