Question

suppose y varies directly with x. write a direct variation equation that relates x and y. then find the value of y when x= 7.

y= -4 when x= 4
equation=

Answer 1

y = kx

To find the value of k, we can use the given data point (x = 4, y = -4):

-4 = k * 4
-4/4 = k
k = -1

Therefore, the direct variation equation that relates x and y is y = -x.

To find the value of y when x = 7, we can substitute x = 7 into the equation:

y = -(7)
y = -7

Therefore, when x = 7, y = -7.