Question

Need help with 13 and 14

Answer 1

Answer:

13. A

14. C.

Step-by-step explanation:

A relation is a function if there is only one y assigned to each x.

That is if you have a set of points, there should be no repeated x value.

So looking at {(0,0),(-2,4),(-2,-4),(-3,7)} this is not a function because you have two x's that are the same. A.

The slope-intercept form of a linear equation is y=mx+b where m is the slope and b is the y-intercept.

The y-intercept is where the graph goes through the y-axis at.  It goes through at -1 so b=-1.

The slope is rise/run.  So starting from the y-intercept (0,-1) we need to find another point to count the rise & run to... How about (3,1)? That works.  You can do the counting if you want. You could also use the slope formula.

To use the slope formula, I just like to line the points up vertically and subtract vertically then put 2nd difference over the 1st difference.

(0,-1)

-(3,1)

--------

-3  -2

So the slope is -2/-3 or just 2/3.

So the equation is y=2/3 x-1

C.