Question

Simple question:

Is this a direct variation?

Age x.... 10, 11, 12, 13
Grade y.... 5, 6, 7, 8

(that's supposed to be a table)

I do not think it is... that's correct, right? You don't get the same thing when you divide 10 and 5 and when you divide 13 and 8

Answer 1

Since both the x and y values increase, then this is direct variation.
Direct variation is written as:
\[y = kx\]
Where k is the constant of variation.
\[5 = k(10)\]
\[k = \frac{1}{2}\]

\[y = \dfrac{1}{2}x\]

What's the issue?

Answer 2

nope... for direct variation... you need

y = kx

each value of x is multiplied by the same value...

Answer 3

if it was direct variation the grade values would be

1/2 x 10 = 5

1/2 x 11 = 5.5

1/2 x 12 =6

etc