It doesn't ! -7 plus -5 equals -12 ! -7 plus 5 equals -2
2+5=7 5+2=7 2+5=5+2
5-x equals 7 = -2
No, 7 - 2 = 5 (not -5)
5+2=7
False; 7-2 is 5.
-5 + 7 = 2
7
5+2 = 7
5a+5=6a-7
12
3x + 2 + 2x = 7; 3x + 2x = 5x, so 5x + 2 = 7; 7-2=5, so 5x=5. 5x divided by 5 and 5 divided by 5 equals 1, so x equals 1.