hello,
In each hour of work, you earn $90. So, we can write this as 90x (x is the time in hours).
You already have $150 in the wallet.
Write an inequality that shows many hours you need to work to earn more than $500
150 + 90x >500
90x > 500 - 150
90x > 350
9x > 35
x > 35/9
x> 3.89 approximately
So, you have to work 4 hours to get some money more than $500.