Substitution for Solving Equations

Homer sells tickets for admission to your school play and collects a total of $104. Admission prices are $6 for adults and $4 for children. He sold 21 tickets total. Solve the system:
x + y = 21
6x + 4y = 104

• (10, 11)

• (12, 9)

• (11, 10)

• (9, 12)

Solve the system of equations using substitution:

-4x + 4y = 8

y = -2x - 10

• (-4, -2)

• (12, -34)

• (4, -18)

• (-2, -6)

Solve the simultaneous equations by substitution

x+y=5

x-y=1

• x=2, y=3

• x=3, y=2

• x=3, y=-2

• x=-3, y=2

Solve the system by substitution:
y = x + 5
4x + y = 20

• (3,8)

• (8,3)

• (0,2)

• (2,0)

What is the first step in solving a system by Substitution?

• Make sure both equations are in standard form.

• Make sure at least one equation is solved for one variable.

• Make sure both equations are in slope-intercept form.

• Make sure both equations can be solved.

• (1, 2)

• (1, 1)

• (2, 1)

• (2, 2)

Using the simultaneous equations 7x+7y=-28 and -4 - 0.875x = 1y, find the solution, giving your answer as a coordinate pair

• (1, -4)

• (0, -4)

• (0, -3)

• (-4, 0)

Christian had brochures printed for a new business venture. Christian originally ordered 4 boxes of black-and-white brochures and 3 boxes of colour brochures, which cost a total of $134. After those ran out, Christian spent $120 on 3 boxes of black-and-white brochures and 3 boxes of colour brochures. Which system represents this situation?

• x+y=134
  x+y=120

• 3x+3y=134
  4x+3y=120

• 4x+3y=134
  3x+3y=120

• 7xy=134
  6xy=120

• (3, 4)

• (4, 3)

• (4, 4)

• (3, 3)

There are 50 donkeys and chickens on a far.  There are a total of 174 legs.  Which system below can be used to figure out how many of each animal the farm has?

• d + c = 174
  4d + 2c = 50

• d + c = 50
  4d + 2c = 174

• d + c = 50
  2d + 4c = 174

• d + c = 174
  2d + 4c = 50