Question

Y varies directly as the square root of x. when y=20, x=16. find the formula for y in terms of x.

Answer 1

y = 5
`√(x)`

Explanation:

given y varies directly as
`√(x)` then the equation relating them is

y = k
`√(x)` ← k is the constant of variation

to find k use the condition when y = 20, x = 16 , then

20 = k
`√(16)` = 4k ( divide both sides by 4 )

5 = k

y = 5
`√(x)` ← equation of variation