Answer:
x must equal 5 and y must equal 2
therefore,
5a + 2b = 23 and
5a - 2b = 7.
I'm gonna take 5a + 2b = 23 and add 7 to each side:
5a + 2b + 7 = 30
and substitute 5a -2b in for 7 on the left side:
5a + 2b + (5a-2b) = 30
10a = 30
a = 3
Now we know a. Now take
5a -2b = 7
and substitute in 3 for a
5*(3) - 2b = 7
15 -2b = 7
8 = 2b
b = 4
a = 3 and b = 4
Explanation: