Question

i am stuck on this problem:
Find the slope and y-intercept of the line represented by the table of values below, then answer the question that follows.
x y
-10 -310
5 80
12 262
19 444
What is the sum of the slope and the y-intercept?
For the y-intecept i got 26 for the slope i got 2 what am i doing wrong and what is wrong and what is right?

Answer 1

first, check to be sure there is a constant slope:

(80+310)/(5+10) = 26
(262-80)/(12-5) = 26
(444-262)/(19-12) = 26

So, the slope is 26

For the y-intercept, since x=0 is 1/3 of the way from 5 to -10, the y-intercept is 1/3 of the way from 80 to -310: -50

26 + -50 = -24

Just to check, we have the slope and intercept, and we can write the equation: y = 26x - 50

The points fit that equation.

Answer 2

no idea what you did wrong, since you didn't bother to show your work.

Answer 3

I really don't get how you got -50 as the y-intercept can you explain more clearer how you got that

Answer 4

Plot the points. It will be clear that the line contains (0,-50).

Or, now that you know the slope, use the point-slope form of the line with any of the points. How about (5,80)

y-80 = 26(x-5)

Now plug in x=0 and you will get y = -50.

Answer 5

Ive gotten it thank you