Question

solve -4 + (-1) + 2 + ......... + x = 437

Answer 1

-4+(-1)+2+____+x=437
-4-1+2+x+x=437
-5+2+2x=437
-3+2x=437
2x=437 +3
2x=440
x=440/2
X=220

Answer 2

a=-4
d=3
sum =437
so
n/2{2*(-4)+(n-1)*3}=437
n/2(3n-11)=437
3n^2-11n=874
3n^2-11n-874

using quadratic formula
-(-11)+-√121+4*3*874/6
-11+-103/6
1st-. -114/6 =-19


so nth term is 19
then x=-4+18*3
x=50

it will help you