Greetings!
Yes, the degree on a monomial can be negative:
Example:

This is equal to:

Hope this helps.
-Benjamin
35 / 5 = 7 ; also 49 /7 = 7
So
? = 8 x 7 = 56
Answer
Missing side length = 56
Answer:
b = 45.9 - c
Step-by-step explanation:
A scalene triangle has non of its sides equal.
Perimeter = 54.6
side a = 8.7 cm
side b = unknown
side c = unknown
Perimeter of a shape is sum of all its sides.
Perimeter = a + b + c
54.6 = 8.7 + b + c
Making b the subject
b = 54.6 - 8.7 - c
b = 45.9 - c
The value of b is (45.9 - c)
21 is the answer.You distribute 6 into the parentheses and you substitute 3 for x so 6(3-1)+9= f(x)=18-6+9 you add all the like terms and the answer is 21