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":

Answer:
65
Step-by-step explanation:
Answer:
228
Step-by-step explanation:
We are adding 3 each time so general rule is
Tn= 3n + 3
Therefore
T= 3(75)+3
= 228
Answer:
b.
Step-by-step explanation:
We have to look at sign changes in f(x) to determine the possible positive real roots.

There is only one sign change here, between the -8x and the +4. So that means there is only 1 possible real positive root.
Now we have to look at sign changes in f(-x) to determine the possible negative real roots.

There are 3 sign changes here. That means there are either 3 negative roots or 3-2 = 1 negative root. So we have:
1 positive
3 or 1 negative
We need to pair them up now with all the possible combinations.
If we have 1 positive and 1 negative, we have to have 2 imaginary
If we have 1 positive and 3 negative, we have to have 0 imaginary
Keep in mind that the total number or roots--positive, negative, imaginary--have to add up to equal the degree of the polynomial. This is a 4th degree polynomial, so we will have 4 roots.