Question

If y varies directly with X and Y 454 when 20. then which equation best represents this proportional relationship? A) y = 0.37xB) y = -0.37x C) y = -2.7xD) y = 2.7x

Answer 1

We need to find the constant of proportionality, so:

y(x) = ax

Where:

a = constant of proportionality

Using the data provided, if x = -20 ; y(-20) = -54, so:

-54 = a(-20)

Solve for a:

Divide both sides by (-20):

-54/-20 = -20a/-20

2.7 = a

a = 2.7

y = 2.7x