math
posted by carol on .
Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this.2x + 2y = 202x – 2y = 4

note that in elimination method, we first simplify/modify one (or both) the given equation until if we add the two given equation, one of the variables will cancel out. in the problem, we can obviously see that the 2y in the first equation will be cancelled out by the 2y of the second. adding them:
2x + 2y = 20
2x – 2y = 4

4x = 24
x = 6
now we substitute this value of x to either equation to get y. let's substitute this to first equation:
2x + 2y = 20
2(6) + 2y = 20
12 + 2y = 20
2y = 8
y = 4
hope this helps~ :)