Which ordered pair would form a proportional relationship with the point graphed below?

On a coordinate plane, a line with negative slope goes through points (negative 20, 10), (0, 0), and (20, negative 10).
(10, –20)
(–30, 20)
(–10, 5)
(35, –20)

Question

Which ordered pair would form a proportional relationship with the point graphed below?

On a coordinate plane, a line with negative slope goes through points (negative 20, 10), (0, 0), and (20, negative 10).
(10, –20)
(–30, 20)
(–10, 5)
(35, –20)

Vocaloid · Answer

The relationship is proportional, so all points can be described with the formula y = kx, where k is a constant

Take any point on the graph (besides 0,0), plug in and solve for k.

Once you have your k-value, go through the answer choices and see which one follows the y= kx rule.