SOLUTION: How do I find y for this equation? 2x-y=1 I don't understand how to solve it and then graph it along with y=-3.

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Question 700783: How do I find y for this equation? 2x-y=1 I don't understand how to solve it and then graph it along with y=-3.
Found 5 solutions by jpvn2015, KMST, ankor@dixie-net.com, Killjoy club, ikleyn:
Answer by jpvn2015(54)   (Show Source): You can put this solution on YOUR website!
2x-y=1
-y=1-2x (subtracted 2x from both sides)
y = -1 + 2x (multiplied both sides by "-1")

Answer by KMST(5328)   (Show Source): You can put this solution on YOUR website!
ONE WAY TO FIND :
--> --> --> --> -->
ANOTHER WAY:
--> --> --> --> -->
Using you can calculate the coordinates of two points on the line,
and then you would just plot the points and connect them with a straight line.

However, you can graph without transforming the equation into .
To get the coordinates of a point on the line,
you can give a value to (or to ),
and solve for the other variable.
For , substituting into we get
--> --> --> .
That gives us the point (0,-1), with and .
For , we get
--> --> --> -->
That gives us the point (3,5).
Plotting (0,-1) and (3, 5} we get
Adding the line, we get


On the line for , all the points have , for any and all values of .
Adding that line (in green), we get:

Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
find y for this equation?
2x - y = 1
subtract 2x from both sides
-y = -2x + 1
y has to be positive, multiply both sides by-1
y = 2x - 1
:
"graph it along with y=-3."
find x when y = -3
2x -1 = -3
2x = -3 + 1
2x = -2
x = 2/-2
x = -1
:
Make a table to plot a graph using above coordinates and x = -3, 0 and +2
x | y
------
-3 |-7; replace x with -3, find y to be -7
-1 |-3
0 |-1
+2 |+3
:
Plot these points, your graph should look like this

Answer by Killjoy club(2)   (Show Source): You can put this solution on YOUR website!

Answer by ikleyn(52776)   (Show Source): You can put this solution on YOUR website!
.
How do I find y for this equation? 2x-y=1 I don't understand how to solve it and then graph it along with y=-3.
~~~~~~~~~~~~~~~~~~~~

1.  Add "y" to both sides. You will get an equivalent equation

    2x = 1 + y.


2.  Subtract "1" from both sides you will get an equivalent equation

    2x - 1 = y.


3.  It is equivalent to 

    y = 2x - 1.


4.  It is your answer.

Solved.

This procedure of three steps is called "to isolate y".


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