Answer:
Part 6) Option B $3.20
Part 7) Option C. 8,295 students
Explanation:
Part 6)
Let
x -----> the cost of one hamburger
y ----> the cost of one soda
we know that
7x+3y=27.95 ------> equation A
5x+4y=23.40 ----> equation B
Solve the system by graphing
Remember that the solution by graphing is the intersection point both graphs
using a graphing tool
The solution is the point (3.2,1.85)
see the attached figure N 1
therefore
The cost of one hamburger is $3.20
Part 7)
Let
x -----> the number of students
y -----> the number of teachers
we know that
x=35y ------> equation A
x+y=8,544-12
x+y=8,532 -----> equation B
Solve the system by substitution
substitute equation A in equation B and solve for y
35y+y=8,532
36y=8,532
y=237 teachers
Find the value of x
x=35y ------> x=35(237)=8,295
therefore
The number of students is 8,295