Algebraic Systems

Kam earned 22 extra credit points. Keith earned e fewer extra credit points than Kam. Type an expression that shows how many extra credit points Keith earned.

Kimi has b buttons. Scott has 72 more buttons than Kimi. Type an expression that shows how many buttons Scott has.

Solve the following system:
3x + 2y = 16
7x + y = 19

• (-2,5)

• (-2,-5)

• (2,-5)

• (2,5)

David is running a concession stand at a soccer game. He sells nachos and sodas. Nachos cost $1.50 each and sodas cost $0.50 each. At the end of the game, David made a total of $78.50 and sold a total of 87 nachos and sodas combined. Which system of equations represents this situation?

• 1.5x+0.5y=78.5
  x+y=87

• 1.5x+0.5y=78.5
  1.5x+0.5y=87

• x+y=78.5
  1.5x+0.5y=87

• x+y=78.5
  x+y=87

Solve for x and y
y = 2x + 1
y = 4x - 1

• (1,3)

• (-1,-3)

• (-1,3)

• (3,1)

What do you do to check a solution to a system of equations?

• Substitute the solution into the first equation only, and see that it works.

• Substitute the solution into the second equation only, and see that it works.

• Ask the point if it is the solution.

• Substitute the solution into both equations, and see that it works.

Solve the following system.  What is the solution?

• (3, -2)

• (3, -3)

• (-3, 2)

• (-3, -3)

One brand of suntan lotion comes in a small size with x ounces of lotion and a regular size with y ounces of lotion.  Given the equations below how can we eliminate the terms with x?
x+2y = 15
2x + y = 19.5

• subtract the two equations from each other

• multiply the second equation by -1 and add the two equations

• multiply first equation by 2, multiply the second equation by 1 then add them

• multiply the first equation by -2 then add the equations together 

What is the solution to this system of equations?

• (4, -1)

• (-1, 4)

• (-4, 1)

• (-4, -1)