In a direct variation, y=39 when x=3. find the value of y when x=2

Direct variation means when one quantity is increased the other also increases or when one quantity is decreased the other also decreases.

Therefore as the variable x is decreased to 2 the variable y is also decreased to 26.

Indirect variation means when one quantity is increased the other decreases or when one quantity is decreased the other is increased.

The variations can be solved by unitary method or cross product method

The cross product method employs the numbers directly .

x: y

3:39

2: k

Here k is the unknown quantity.

Using the cross product rule

3 × k= 2× 39

k= 78/3= 26

The missing value of k is found to be 26.

link

y = 26

The equation for direct variation is y = kx ← k is the constant of variation

to find k use the condition y = 39 when x = 3

k = = = 13

equation is y = 13x

when x = 2 then y = 13 × 2 = 26

a. -0.3 > -0.33