So she earned 84 total dollars
she earned 14 dollars mowing lawns
she earned (total-mowing lawns=babysitting) 84-14=70 dollar babysitting
7 dollars per hour so
70/7=10 so
h=10
To put it into an equation, it would be:
340 = 2x - 100
with x being the amount of sophomores at BHSS.
Solve it:
340 + 100 = 2x
2x = 440
x = 220
The number of sophomores at BHSS is 220.