Question

Which equation represents the line passing through the points (3, 2) and (−9, 6)?

x − 3y = 9

x + 3y = 9

3x − y = −9

3x + y = 9

Answer 1

Plug in the variables (3, 2) and (−9, 6).

x − 3y = 9
(3)-3y = 9
-3y = 6
y = -2
Not the equation.

x + 3y = 9
(3) + 3y = 9
3y = 6
y = 2
(-9) + 3y = 9
3y = 18
y = 6
This is the equation.

3x − y = −9
3(3) - y = -9
y = 18
Not the equation.

3x + y = 9
3(3) + y = 9
y = 0
Not the equation.