Question

Find the constant of variation for the relation and use it to write an equation for the statement. Then solve the equation

If y varies directly as x, and Y = 7 when x = 3, find y when x = 7.
2 y=-2, 217) – 4
cy=; y(7) – 343
d. y=72: v(7) =49
5. y= 22,00)=2

Answer 1

y =
`(49)/(3)`

Explanation:

Given that y varies directly as x then the equation relating them is

y = kx ← k is the constant of variation

To find k use the condition y = 7 when x = 3

k =
`(y)/(x)` =
`(7)/(3)`, thus

y =
`(7)/(3)` x ← equation of variation

When x = 7, then

y =
`(7)/(3)` × 7 =
`(49)/(3)`