Question

The 10th term of an AP is 3 times the 3rd term and exceed by 28 find the first term​

Answer 1

a + 9d = 3( a + 2d )

a +9d = 3a + 6d

2a = 3d

a = 1.5da

a + 9d = a + 2d + 28

7d = 28

d = 4

a = 6