Answer:

Step-by-step explanation:
Let
denotes number of pencils, markers, erasers respectively.
For Andrea:

For Justin:

For Virginia:

On subtracting equations (i) and (ii), we get

Put
in equation (i)

Put
in equation (iii)

Multiply equation (iv) by 5 and equation (v) by 6 and then subtract both the equations.

Put
in equation 

Put
in equation (i)

X + 9/7 = 10
- 9/7 -9/7
___________
x = 8 2/7
Answer:
B) -7
Step-by-step explanation:
x+y
8+(-15)=8-15=-7
Answer:
A) 2
Step-by-step explanation:
Start off with the given information. The question states that the x-int. is 4, so you should recognize that there is a point at (4,0). Plug the point into the equation.
k(4) + 2(0) + 8 = 0
Now simplify the equation.
4k + 0 + 8 = 0
Isolate the variable, make sure it's on its own side.
4k = 8
Now get the k by itself to solve the equation. Divide both sides by 4.
k = 2
Answer:
i got 4 but idk if its roght srry give it an try