Question

if y varies directly as x and y=8 when x=4, what is the value of y when x=16?
a. 32
b. 16
c. 64
d. 28

Answer 1

y varies directly as x

so \(y \quad\alpha \quad x\)
we can take constant of proportionality as 'k'

so,
y =kx

Answer 2

now
y=kx

when y =8, x=4

plug these in,
and tell me the value of 'k'!

Answer 3

C