If y varies directly with x, find the value of y when x = 27 for the direct variation with the given information. y = 7 when x = -9 y =

Question

asked Jun 10, 2022 124k views

1 Answer

Eugene Chow · Answer 1 · 2022-06-16T02:43:19+0000

Given:

y varies directly with x,

It is given that y = 7 when x = -9.

To find:

The value of y when x = 27 for the direct variation.

Solution:

It is given that y varies directly with x, so

$y\propto x$

y=kx ...(i)

Where, k is the constant of proportionality.

It is given that y = 7 when x = -9. Putting these values in (i), we get

7=k(-9)

-(7)/(9)=k

Putting
k=-(7)/(9) in (i), we get

y=-(7)/(9)x

Putting
x=27 , we get

y=-(7)/(9)(27)

y=-21

Therefore, the required value is
.