Answer:
Cost of one pencil: 
Cost of one eraser: 
Step-by-step explanation:
Let be "p" the cost in dollars of one pencil and "e" the cost in dollars of one eraser.
Based on the information given in the exercise, you can set up the following system of equations:

You can use the Elimination Method to solve the system of equations.
Multiply the first equation by -3 ad the second one by 4. Then add the equations and solve for "e":
{
Substitute the value of "e" into any original equation and solve for "p":

I think you meant to add more to your question (posting the specific problem).
In general, one special right triangle is the <span>45°-45°-90° triangle, in which both legs are congruent and the hypotenuse = √2 * the length of the leg. if you happen to not have the length of the leg, the formula for finding the leg is: leg = hypotenuse / √2
Another special right triangle is the </span><span>30°-60°-90° triangle. With this kind of triangle the length of the hypotenuse is twice the length of the shorter leg. The length of the longer leg is √3 times the length of the shorter leg.
hypotenuse = 2 * shorter leg
longer leg = √3 * shorter leg</span>
Answer:
$20
Step-by-step explanation:
the manager's error could likely be putting the percentage mark up rather than the markup price added to the original price
25%×16
= $4
mark up price= (16+4)$
= $20
Answer:
Step-by-step explanation:
x=14 is a vertical line with undefined slope
It has no y intercept and has only x intercept of 14.