solve for x. :-
(I) 1+6+11+16+.....+x = 148
(ii) 2.5 + 22+19+16+...+x= 115
Answers
Answered by
6
the second one is solve like first only
Attachments:
latav2006p1x6u7:
U did wrong coz. 1)59.5. 2)75.5 is the correct answer I even asked my tutor...
i think it is right
and if it is wrong then send the right one
Factorization of 5n² -3n - 296 is wrong......
i think it's right.
Answered by
1
For (i)
a=1 , d=5 & l=x
Tn=x
a + (n-1)d=x
1 + (n-1)5=x
1 + 5n - 5 = x
5n - 4 = x
n= (x+4)/5
Now,
Sn = n(a+l)/2
148= (x+4)(1+x)/10
1480= x² +x + 4x + 4
0= x² +5x -1476
0= x² + 41x - 36x -1476
0 = x(x+41)-36(x+41)
0= (x+41)(x-36)
(x+41)=0 or (x-36)=0
x= -41 or x=36
Value of x can't be negative.
So, x=36
Similarly we can solve (ii) question.
Similar questions