Algebra 1 Systems of Equations

Solve the system of equations by graphing.

Answer explanation

Solve the system of equations by elimination.
-x + y = -13
-8x - 4y = -8 

• (5, 8)

• (5, -8)

• (-5, -18)

• (-5, 8)

Solve for x and y

YOU CHOOSE WHICH METHOD

3x + 2y = 16 7x + y = 19

• (-2,5)

• (-2,-5)

• (2,-5)

• (2,5)

The sum of Mr. Micklow and Ms. Craft's age is 55.  The difference is 3.  
Solve:
x + y = 55
x - y = 3

• (26, 23)

• (26, 29)

• (29, 26)

• (29, 32)

SOLVE BY SUBSTITUTION

y = -6x + 5

-2x + y = 5

• (-3, -6)

• (-6, 3)

• (0, 5)

• (-3, 5)

SOLVE BY SUBSTITUTION

y = -3x + 11

5x + y = 21

• (1, -5)

• (1, 5)

• (-4, 5)

• (5, -4)

Solve by elimination 
  2x + 9y = -7
6x - 3y = 9 

• (-1, -1) 

• (2,-1)

• (1,1)

• (1,-1)

How many solutions?

• One Solution

• No solution

• Infinitely Many Solutions

When you graph the exact same equation twice,

• you will have no solution. 

• you will have one solution.

• you will have infinite solutions. 

• you will graph a giraffe. 

Amy sold 10 packages of sugar cookies and 2 packages of oatmeal cookies for $56. Adam sold 9 packages of sugar cookies and 3 packages of oatmeal cookies for $60. What is the price of 1 pack of sugar cookies and 1 pack of oatmeal cookies?

• Sugar Cookies $5 
  Oatmeal Cookies $3

• Sugar Cookies $4
  Oatmeal Cookies $8

• Sugar Cookies $2
  Oatmeal Cookies $6

• Sugar Cookies $3
  Oatmeal Cookies $6