Answer:
b
Step-by-step explanation:
took the test i got bj : fz wf
The least number of classes needed for all the students to be registered in a class is 21 classes.
Answer: There are 99 three-legged-cows and 28 chickens.
Step-by-step explanation:
Let x be the number of three-legged-cows and y be the number of chickens.
Number of legs in chicken = 2
The according to the question, we have the following equations :-

Multiplying 2 to the equation (1), we get

Now, subtract equation (3) from (2), we get

Put x= 99 in (1), we get

Hence, there are 99 three-legged-cows and 28 chickens.
The solution to a system of equations is the point on a graph where the two lines intersect. The graph where the point of intersection is (2, -1) is the last graph. The last graph is the correct answer.
HOPE THIS HELPS!! PLEASE MARK BRAINLIEST