Question 816881: please help......solve the following system of equations by graphing: 2x-y=8
y=2
and please show step by step work.. I tired it on my own but I could not figure it out
Thank you
Answer by LinnW(1048)   (Show Source):
You can put this solution on YOUR website! First solve the first equation for y.
2x-y=8
Subtract 2x from each side.
-y = -2x + 8
Multiply each side by -1
y = 2x -8
To plot this equation, use the fact that the y
intercept is (0,-8). Since the slope is 2,
beginning at the point (0,-8) move to the right 1
and up 2. You will now be at the point (1,-6).
Draw a line through (0,-8) and (1,-6).
Now graph the line y=2. This is just a horizontal
line 2 units above the x axis.
Where the two lines intersect is the solution.
You can check your solution by considering
the two equations
y=2 and y = 2x -8
Set the right hand sides to be equal
and we have
2 = 2x - 8
Add 8 to each side.
2 + 8 = 2x - 8 + 8
10 = 2x
So x = 5. Of course y = 2 .
|
|
|
