Question

Which equation represents the function whose data is shown in the table?

A. y =2x +1


B.y = x -1


C.y = x+1


D.y = 2x -1

Answer 1

Then the answer is D), because in the equation y=2x-1, it is raising by 2 and the y-intercept is (0,-1)

Answer 2

Slope intercept form is:

y = mx + b

"m" is the slope, "b" is the y-intercept(the y value when x = 0)

To find "m" you can use the slope formula:

$m =\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$

And plug in 2 points from the table. I will be using the points (1 , 1) and (2, 3)

$m =\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$

$m = \frac{3-1}{2-1} =\frac{2}{1}=2$

y = 2x + b

In the table, when x = 0, y is -1. So your y-intercept is -1

y = 2x - 1

Your answer is D