Answer: C. 120
Step-by-step explanation:
14/21 will get you 66.6. Taking that number and multiplying it by the 180 total students will end you with 120 which is your answer.
For this case we have the following system of equations:

Equating both equations we have:

We must find the solutions, for this we factor. We look for two numbers that, when multiplied, result in 4 and when added, result in 5. These numbers are 4 and 1:

Then, the factorized equation is of the form:

Thus, the solutions are:

We look for solutions for the variable "y":

Thus, the system solutions are given by:
ANswer:

Answer:
The total amount of lawns to be mowed would be 20 in 35 hours.
Step-by-step explanation:
It takes an hour and 45 minutes to mow one lawn. When you multiply the 7 hours by 5 you get 35 hours. Same thing if you multiply the 4 lawns by 5 you get 20 lawns.
So u multiply each term in the first parentheses by each term in the second parentheses.
√5 √5 + 6√5-3√5 - 3x6
Now you multiply the numbers which will get u:
5+6√5 - 3√5 - 18
Then subtract:
-13 +3√5 that’s your answer