Solving Systems of Equations by Graphing

Is (1,10) a solution to

y=7x+5

y=x+9

• yes

• no

A large pizza at Palanzio’s Pizzeria costs $6.80 plus $0.90 for each topping. The cost of a large cheese pizza at Guido’s Pizza is $7.30 plus $0.65 for each topping. Which system of equations could be used to find the number of toppings when both companies cost the same amount?

• y = 6.80 + .65x
  y=7.30+.90x

• x + y = 6.80
  x + y = 7.30

• y = 6.80+.90x
  y = 7.30 + .65x

• y + .90x = 6.80
  y + .65x = 7.30

Some students want to order shirts with their school logo. One company charges $9.65 per shirt plus a setup fee of $43. Another company charges $8.40 per shirt plus a $58 fee. Which equation represents the number of shirts when both companies charge the same amount?

• y = 9.65 + x
  y = 8.40 + x

• y = 9.65x + 43
  y = 8.40x + 58

• y =9.65x
  y = 8.40x

• y = 9.65x - 43
  y = 8.40x - 58

Solve by elimination:
4x + 9y = 28
-4x - y = -28

• (-7,0)

• (6,0)

• (-6,0)

• (7,0)

Solve the system given:
-x + y = -4
y = 2x - 11

• (3,7)

• (7,3)

• (4,-3)

• (-3,4)

Solve the system of equations.

• (-34, -17)

• (8, 4)

• (10, 20)

• No solution

• Infinite solutions

Determine how many solutions the system has.

• One Solution

• No Solutions

• Infinitely Many Solutions

• Mikey is my friend.

Determine how many solutions the system has.
(Hint:  Both lines are graphed over each other)

• One Solution

• No solution

• Infinitely Many Solutions

• I am Spartacus!

What is the solution to the system?

• (0, 3)

• (1, -1)

• (-3, 1)

• (1, 3)

Solve the system by graphing:

y=2x-3

y=1/2x

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