Question

Look at the table of values below.

x y
1 -1
2 -3
3 -5
4 -7

Which equation is represented by the table?
y = 1 − 2x
y = -x − 1
y = x − 2
y = 2x − 1

Answer 1

Hello,

Answer A
(1,-1)
(2,-3)
m=(-3+1)/(2-1)=-2

y+1=-2(x-1)==>y=-2x+1

Answer 2

y = 1 − 2x

Explanation:

If you observe the given table, you would find that as x-values increase by one, y-values decrease by 2. This ratio of change can be found as the following,

`r=(-7-(-1))/(4-1)=(-7+1)/(3) =(-6)/(3)=-2`

The ratio of change is -2, which means the function is decreasing, beacuse its slope is negative.

Now, we can use the slope, one point and the point-slope formula, to find the equation that models those values

`y-y_(1) =m(x-x_(1) )\\y-(-1)=-2(x-1)\\y+1=-2x+2\\y=-2x+2-1\\y=-2x+1\\y=1-2x`

Therefore, ther right answer is the first choice.