Monomial, it has 1 term ad it is sipmlified
answe is A
4x+15y=13 (1)
3x+5y=16 (2)
(2) * 3 --> 9x+15y=48 becomes (3)
(3) - (1)
5x=35
x=7
sub x =7 into (1)
4(7)+15y=13
28+15y=13
-28 -28
15y= -15
y= -15/15
y= -1
therefore x=7 and y= -1
Answer:

Step-by-step explanation:
Since there are 20 students, this will be the denominator.
Now, to find how many students have a dog and a cat, you need to subtract all the numbers with 20. The leftover number will be the amount of students.
7+8+8=23
23-20=3
So, there are 3 students who have a dog and a cat.
So, the fraction will be 
Use y=mx+b It helped me so much