Hi Tracey;
x+y=2
3x2y=9
The coefficient of x in the second equation is 3.
The coefficient of y in the second equation is 2.
Let's take the first equation and multiply both sides by either coefficient. I randomly choose 3...
3(x+y)=(2)(3)
3x+3y=6
Let's subtract one equation from the other...
3x+3y=6
(3x2y=9)
0+5y=15
Please remember that subtracting a negative number is the same as adding a positive number...
3y2y=3y+2y=5y
69=6+9=15
5y=15
Let's divide both sides by 5...
(5y)/5=15/5
y=3
Let's input this result into either equation to establish the value of x. I randomly choose the first. I will use its original form...
x+y=2
x+3=2
Let's subtract 3 from both sides...
x+33=23
x=1
Let's take the second equation and verify the results...
3x2y=9
[(3)(1)][(2)(3)]=9
36=9
9=9
2/19/2014

Vivian L.