Question

For the data in each table tell whether y varies directly with x if it does write an equation for the direct variation x|y
-3|-7.5
-1|2.5
2|-5
5|-12.5

Answer 1

yes, y varies directly with x.

y=4x is an equation of the Direct Variation

Step-by-step explanation:

x y

0 0

1 4

2 8

3 12

From the above data:

we can say that y varies directly with x.

Direct variation states that if y is expressed as the product of some constant number k and x.

i.e y=kx

Now, let any points from above data x= 2 and y= 8 to calculate the value of k,

8=2k

⇒

Therefore, the equation for the direct variation is, y=4x

Answer 2

If only the first one were
-3 | +7.5
it would work with y = -2.5 x
However as it is written he slope is NOT constant