So scientific notation is making the number manageable.
scientific notation is
(a number >1 and <10) times 10^x
we count how many places the decimal has to move to make the number >1 and >10.
the answer is 6.
5.74 times 10^6
1. H+S=40
2. 19H+25S=922
From 1,
19H+19S=760
Subtract this from 2 to eliminate H,
19H+25S-19H-19S=922-760
6S=162
Solve for S, then use either equation to solve for H.
See the image below for a demonstration. Hope this helps out.