Answer: C. 

Step-by-step explanation:
If 't' represents the number of hours Joanne tutors and 'r' represents the number of hours she works as a receptionist.
Then the total hours she can work=t+r
Since she can work up to 25 hours.
Thus 
If she earns $25 per hour by tuition and $ 12 per hour by working as a receptionist .
Then her total earning =$
Since she must earn $200.
Then
.
Therefore, the required system of inequality will be


The process of finding which prime numbers you need to multiply together to get a certain number. ex: 21=7x3 20=2x2x5
1.Simplify.
-2{x}^{2}-4x+13+12{x}^{2}+2x-25−2x2−4x+13+12x2+2x−25
2.Collect like terms.
(-2{x}^{2}+12{x}^{2})+(-4x+2x)+(13-25)(−2x2+12x2)+(−4x+2x)+(13−25)
3.Simplify.
10{x}^{2}-2x-1210x2−2x−12
Here, I think I can help you out:
1. 21 ÷ 3
= 7
Therefore, the length is 7cm².
2. 35 ÷ 7
= 5cm²
- And so on. Simply divide the area by the length of the side given; you can answer up to question six using this strategy.
7. All sides of a square are the same length.
7 x 7
= 49cm²
9. 2 x 3.5
= 7m²
- The formula to find the area of a square/rectangle is length x width. Just multiply the given lengths for the answers :)