Question

If y varies directly as x and y=3 when x=4. Find :

Connecting law
X when y=9
Y when x=2

Answer 1

x = 12 and y = (3/2)

Explanation:

"Y varies directly as x," can be written as:

y = mx

The connecting law is m, which relates how much y will change for a change in x. m is given by:

m = y/x

To find m, the slope, use the two given values for x and y:

m = y/x

m = 3/4

This yields:

y = (3/4)x

Now we can find:

X when y=9:

y = (3/4)x

9 = (3/4)x

x = (4/3)*9

x = 12

Y when x=2:

y = (3/4)x

y = (3/4)*2

y = (3/2)