Answer:
A. a rectangle and a triangle
Answer:
Cost of each hat: $5
Cost of each mask: $3
Step-by-step explanation:
Let be "x" the cost in dollars of a party hat and "y" the cost in dollars of a mask.
Set up a System of equations using the information given in the exercise:

You can use the Elimination Method to solve this System of equations:
1. You can multiply the first equation by -1.
2. Then you must add the equations.
3. Solve for "y".
Then:

4. Now you can substitute the value of "y" into any original equation.
5. Finally, solve for "x" in order to find its value.
Then:

Answer:
You mean improper fraction?
3 x 8 = 24
24 + 3 = 27
27/8
Answer:
B= 2y(3)/7x(8)
C= 12/ x(3) y(3)
D= The same because nothing else can be done with it
(parnthaces) are exponents
Answer:
In mathematics, the determinant is a scalar value that is a function of the entries of a square matrix. It allows characterizing some properties of the matrix and the linear map represented by the matrix.