Question

write the equation of the line passing through the two given points (-1,2) and (4,7)​

Answer 1

First of all, remember what the equation of a line is:

y = mx+b

Where:

m is the slope, and

b is the y-intercept

where m=(y2-y1)/(x2-x1)

x1=-1 , y1=2 & x2=4 , y2=7

m=(7-2)/(4+1)

m=5/5

m=1

So, we have the first piece to finding the equation of this line, and we can fill it into y=mx+b like this:

y=1x+b

now we need to get b value

You can use either (x,y) point you want..the answer will be the same:

(-1,2). y=mx+b or 2=1 × -1+b, or solving for b: b=2-(1)(-1). b=3.

(4,7). y=mx+b or 7=1 × 4+b, or solving for b: b=7-(1)(4). b=3

The equation of the line that passes through the points

(-1,2) and (4,7)

is

y=1x+3