maths
posted by festus on .
the sum of the 4th and 6th terms of an A.P is 42. the sum of the 3rd and 9th terms of the progression is 52. find the first term, the common difference and the sum of the first ten terms of the progression.

what don't you get?
T4 = a+3d
T6 = a+5d
a+3d + a+5d = 42
2a + 8d = 42
a+4d = 21
T3 = a+2d
T9=a+8d
a+2d + a+8d = 52
2a + 10d = 52
a+5d = 26
a+4d = 21
a+5d = 26
d = 5
so a=1
sum of T1T10 = 10/2(1+46) = 235
AP = 1 6 11 16 21 26 31 36 41 46 . . . 
Answer