c. yes; y = 3.5x
To determine if y varies directly with x, check if the ratio of y to x is constant.
28/8 = 3.5
56/16 = 3.5
70/20 = 3.5
Since the ratio is constant (3.5), y varies directly with x and the equation for the direct variation is y = 3.5x
For the data in the table, does y vary directly with x? If it does, write an equation for the direct variation.
x y
8 28
16 56
20 70
(1 point)
Responses
a. yes; y = 5x
b. yes; y = x + 20
c. yes; y = 3.5x
d. no; y does not vary directly with x
1 answer