The system is
2x + y = 8
x - y = 1
Let's solve this system using some of the steps outlined above.
1. Solve the first equation for y. To do this, subtract 2x from both sides:
0 + y = 8 - 2x => y = 8 - 2x
2. Now let's look at the second equation. See that y? We write out the
equation like this: x - ( y ) = 1
(Must use those parentheses!)
Whre you see y, write 8-2x instead:
x - ( 8-2x) = 1
3. Simplify this: x - 8 + 2x = 1
4. Combine like terms: 3x - 8 = 1; add 8 to both sides to isolate x:
5. Isolate x: 3x = 9
6. Sove for x: x = 3. Because x - y = 1, 3 - y = 1, so y must be 2.
7. Set out the solution: It's the point (3, 1).
Plese compare this solution with the one giv en in this problem. Can you find any errors in Jenny's approach? Please respond.
