SOLUTION: 1. Find an equation of the line containing the points (-2,1) and (8,11); slope-intercept form. 2. Find an equation of the line containing the points (2,-1) and (5,1); standard f

Algebra ->  Graphs -> SOLUTION: 1. Find an equation of the line containing the points (-2,1) and (8,11); slope-intercept form. 2. Find an equation of the line containing the points (2,-1) and (5,1); standard f      Log On


   

Question 1155234: 1. Find an equation of the line containing the points (-2,1) and (8,11); slope-intercept form.
2. Find an equation of the line containing the points (2,-1) and (5,1); standard form.
Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

1. Find an equation of the line containing the points (-2,1) and (8,11); slope-intercept form.
y=mx%2Bb
use given points to find a slope
m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29
m=%2811-1%29%2F%288-%28-2%29%29
m=10%2F%288%2B2%29
m=10%2F10
m=1

y=x%2Bb.....use one point to find b
1=-2%2Bb
b=1%2B2
b=3

equation is:
y=x%2B3


2. Find an equation of the line containing the points (2,-1) and (5,1); standard form.
y=mx%2Bb
use given points to find a slope
m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29
m=%281-%28-1%29%29%2F%285-2%29
m=%281%2B1%29%2F3
m=2%2F3
y=%282%2F3%29x%2Bb...use one point to find b
-1=%282%2F3%292%2Bb
-1=4%2F3%2Bb
-1-4%2F3=b
b=-3%2F3-4%2F3
b=-7%2F3

y=%282%2F3%29x-7%2F3......both sides multiply by 3
3y=2x-7
-2x%2B3y=-7-> standard form

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.

At this site,  there is a group of lessons related to this class of problems

    - Find the slope of a straight line in a coordinate plane passing through two given points
    - Equation for a straight line having a given slope and passing through a given point
    - Solving problems related to the slope of a straight line
    - Equation for a straight line in a coordinate plane passing through two given points (*)
    - Equation for a straight line parallel to a given line and passing through a given point
    - Equation for a straight line perpendicular to a given line and passing through a given point

    - OVERVIEW of lessons related to the slope of a straight line

The most relevant to your current problem is the lesson marked  (*)  in the list.
So start from this lesson.

But if you want to learn the subject in all its aspects,  you need to learn all these lessons.

Consider them as your textbook,  handbook,  tutorials and  (free of charge)  home teacher.