Answer:
[tex]x\geq 50[/tex]
Step-by-step explanation:
Let x be number of tickets that still need to be sold.
We have been given that tickets to a school dance cost $5. So cost of x tickets will be 5x.
We have been given that 90 tickets have already been sold. Therefore, cost of 90 tickets will be 90*5.
We are told that at least $700 must be earned from selling of tickets. So price of 5x plus 90*5 must be greater than or equal to 700.
Let us represent this information in an inequality.
[tex]5x+90\cdot 5\geq 700[/tex]
[tex]5x+450\geq 700[/tex]
[tex]5x\geq 700-450[/tex]
[tex]5x\geq 250[/tex]
[tex]x\geq \frac{250}{5}[/tex]
[tex]x\geq 50[/tex]
Therefore, at least 50 tickets must be sold to earn at least $700.