What is the equation of the line through (2,3) and (0, -1)

Question

I need an answer ASAP thank you.

Answer 1

Use the two-point form:

 

(y - y₁) / (x - x₁) = (y₁ - y₂) / (x₁ - x₂)

 

(y - 3) / (x - 2) = (3 - (-1)) / (2 - 0)

(y - 3) / (x - 2) = 4/2

2(y - 3) = 4(x - 2)

2y - 6 = 4x - 8

2y = 4x - 2

y = 2x - 1

Answer 2

Hi Sophia,

 

To solve this first you need to calculate the slope: (y2-y1)/(x2-x1) using the 2 points you have. So (-1-3)/(0-2)=2. 

Then we can write the equation y=2x+b. To solve for b, just plug in one of the points that needs to be on the line. 

 

-1=0(x)+b. b=-1. Your equation is therefore y=2x-1.