Pallavi P.

Per.7

Computer Project #1

System: 2x + 2y=8

3x + 2y=12

I decided to solve this problem by using the process of elimination. In this procedure, the first step is to cancel out one variable using addition or subtraction. For this particular system, I cancelled out the y by subtracting

2x + 2y = 8

- (3x + 2y = 12)

After subtracting one equation from the other I got –x = -4. I then multiplied each side by –1 and got the answer x = 4 like below:

-x = -4

(-1) (-1)

x = 4

I now knew that the x coordinate was 4. Next I had the find the y coordinate. To do this, I just substituted the variable x with 4 in one of the equations:

2x + 2y = 8

2(4) + 2y = 8

8 + 2y = 8

-8 -8

2y = 0

2 2

2 2

y = 0

After solving this equation I found that the y coordinate was 0. If the x coordinate was 4 and the y coordinate was 0, then the solution of the system is the point (4,0).

Another way to solve this problem is to make a graph. By using the two equations in the system as linear equations (y = mx + b) you can draw two lines. For this system the equation 2x + 2y = 8 would be y = -x + 4 as a linear equation and 3x +2y = 12 would be y = -1.5x + 6. The point at which the two lines cross (the break-even) will be the solution. For this problem the solution is (4,0).