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)

Answer:
10 cm
Step-by-step explanation:
From the diagram,
Applying,
lw = 5/2(bh)..................... Equation 1
Where l = length of the rectangle, w = width of the rectangle, b = base of the triangle, h = height of the triangle.
make w the subject of the equation
w = 5(bh)/2l............... Equation 2
From the diagram,
Given: l = 12 cm, b = 6 cm, h = 8 cm
Substitute into equation 2
w = 5(6×8)/(2×12)
w = 10 cm
Hence the width of the rectangle is 10 cm
Px + qy = r
2px - qy = 2r
----------------add
3px = 3r
x = 3r/3p
x = r/p
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Hi my lil bunny!
❧⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯☙
Let's solve your equation step-by-step.

Step 1: Simplify both sides of the equation.

(Combine Like Terms)

Step 2: Subtract 5 from both sides.

Step 3: Divide both sides by -1.

Answer : 
❧⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯☙
●✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎❀✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎●
Have a great day/night!
❀*May*❀
<span>Based in the information given in the problem, you must apply the The Angle Bisector Theorem. Let's call the triangle: "ABC"; the internal bisector of the angle that divides its opposite side: "AP"; and "x": the longest and shortest possible lengths of the third side of the triangle.
If BP= 6 cm and CP= 5 cm, we have:
BP/CP = AB/AC
We don't know if second side of the triangle (6.9 centimeters long) is AB or AC, so:
1. If AB = 6.9 cm and AC = x:
6/5 = 6.9/x
x = (5x6.9)/6
x = 5.80 cm
2. If AC= 6.9 cm and AB= x:
6/5 = x/6.9
x = 6.9x6/5
x = 8.30 cm
Then, the answer is:
The longest possible length of the third side of the triangle is 8.30 cm and the and shortest length of it is 5.80 cm.</span>