Question

Which equation is satisfied by all of the plotted points?


A. y = 3x
B. y = -3x
C. y = -2x -1
D. y = 3x + 1
E. y = x + 3
F. y = 2x + 1

Answer 1

The line passes through the origin which implies the y-intercept is zero.
That rules out all equations that have a non-zero y-intercept (Note: In y = mx + b, b is the y-intercept. If b is present in any equation and it is not zero, then those equations can be ruled out).
Next, the slope of the straight line is positive. Therefore, the "m" in y = mx + b must be positive. Only one answer choice satisfies this and the above requirements.

Answer 2

I learned it today but the teacher didn't really go through it. I know that Y=mx+b is the method to doing it.