What makes a point a solution to a system of two inequalities

3boys + 4 girls = 7 students

3 boys to students   true   yes

4 girls to 3 boy   true     yes

3 boys to 7 girls   false   no

4 girls to 7 students   true   yes

question

why are the following expressions not monomials?

1) 3cd^x

a. the variable is in the denominato

2) x+2w

c. the expression is not a product.

3) 3/h

a. the variable is in the denominator

4) ab^-1

c. the expression is not a product.

hope this !