A teacher grades 27 tests in 3 hours Find the constant of variation

Step-by-step explanation:

Step one:

given

Let the number of tests graded be g = 27

time taken t = 3 hours

Required

The constant relating the time and the number of tests

Step two:

"The constant of variation is the number that relates two variables that are directly proportional or inversely proportional to one another."

so that the direct variation is

g∝kt

g=t/k

k= g/t

k=27/3

k=9

y=−9/2x+10

step-by-step explanation:

let's solve for y.

0−9x−2y=−20

step 1: add 9x to both sides.

−9x−2y+9x=−20+9x

−2y=9x−20

step 2: divide both sides by -2.

−2y

−2

=

9x−20

−2

y=

−9

2

x+10