Maths: logarithm?

1.
2 log(x,10) - 4 log(1000,x) = 5
2 log(x,10) - 12 log(10,x) = 5
2 log(x,10) - 12/log(x,10) = 5
2 [log(x,10)]^2 - 5 log(x,10) - 12 = 0
[2 log(x,10) + 3][log(x,10) - 4]=0
log(x,10)= - 3/2 or 4
x = 1/(10√10) or 10000 ....Ans


2.
log(x,3) + log(x,5)=2.3
log(x,10)/log(3,10)+log(x,10)/log(5,10)=2.3
log(x,10)(0.6990+0.4771)=2.3*0.4771*0.6990
log(x,10)~0.6522 ....
x~4.4895