Question

Determine a relationship between the x- and y-values . Write the resulting equation

[(2,3),(3,5),(4,7),5,9)]
A. y=3x-1
B. y=x+1
C. y=x-1
D. y=2x-1

Answer 1

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

Formula to find slope is

`m=(y_(2)-y_(1))/(x_(2)-x_(1))`

Let's take first two points (2,3) and (3,5) to find the equation. So, plug in x1=2, y1=3, x2=3 and y2=5 in the above formula. So,

`m=(5-3)/(3-2)`

`m=(2)/(1)`

So, m=2

Point-slope form of a line is:

`y-y_(1) =m(x-x_(1) )`

So, next step is to plug in x1=2, y1=3 and m=2 in the above equation. Hence,

y-3=2(x-2)

y-3=2x-4

y= 2x-4+3

y=2x-1

Hence, the correct choice is D: y=2x-1