If the first three terms of an arithmetic progression are (x+3). (3x-10) and (2x+12), find x.
+16 d = common difference
x+3+d = 3x-10
d = 2x-13
3x-10+d = 2x+12
d = -x + 22
2x-13 = -x+22
3x = 35
x = 35/3
Checking answer:
35/3 + 9/3 = 44/3
35-10 = 25 = 75/3
70/3 + 12 = 70/3 + 36/3 = 106/3
106/3 - 75/3 = 31/3
75/3 - 44/3 = 31/3
x = 35/3
