Soo :
2a + 3b = 325
2a + 7b = 505 -
-4b = -180
4b = 180
b = 45
2a + 3(45) = 325
2a + 135 = 325
2a = 325 - 135
2a = 190
a = 95
1.6m questions
2.0m answers