Question

Pls help me do I need it under 20min thank u​

Answer 1

see explanation

Explanation:

(a)

given y varies directly with T and inversely with x² , then the equation relating them is

y =
`(kT)/(x^2)` ← k is the constant of variation

to find k use the condition y = 5 when T = 2 and x = 4

5 =
`(2T)/(4^2)` =
`(2k)/(16)` ( multiply both sides by 16 )

80 = 2k ( divide both sides by 2 )

40 = k

y =
`(40T)/(x^2)` ← equation of variation

(b)

when T = 3 and x = 4 , then

y =
`(40(3))/(4^2)` =
`(120)/(16)` = 7.5