CA #3 Study Guide

Solve the system of equations by graphing.
y = -4x + 5
y =  3x - 16

• (-3, -25)
• (3,-7)
• (11, 17)
• (21, 47)

Tags

CCSS.8.EE.C.8B

Alexandra finds that she can give 3 haircuts and 2 hair dyes in 315 minutes. Giving 2 haircuts and 4 hair dyes takes 450 minutes. Which system of equations represents the situation? How long does it take to complete one hair cut?

• 3x + 2y = 315

  2x + 4y = 450

  It takes 45 minutes to complete one hair cut

• 3x + 2y = 450

  2x + 4y = 315

  It takes 90 minutes to complete one hair cut

• 2x + 2y = 315

  3x + 4y = 450

  It takes 4 minutes to complete one hair cut

This system has _____ solutions

• 0
• 1
• 2
• Infinitely many

Tags

CCSS.8.EE.C.8B

What is the solution?

• (1, -1)
• (-1, 1)
• (0, -2)
• (0, 1)

Tags

CCSS.8.EE.C.8A

Does the system have one, none or infinite solutions?
8x + 4y = 12
y = -2x + 3

• (0,3)
• (3,0)
• No solution(parallel lines)
• Infinitely many solutions

Tags

CCSS.8.EE.C.8B

Solve the system given:
3x - y = 7
2x + y = 3

• (-1,2)
• (5,4)
• (4,5)
• (2,-1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the best method to use?

2x − 3y = −1

y =x − 1

• Graphing

• Substitution because a variable is defined

• Elimination because the equations are in standard form.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the best method to use?

−4x − 2y = −12

4x + 8y = −24

• Graphing

• Substitution because a variable is defined

• Elimination because the equations are in standard form.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the proper way to set up the equation to begin solving?

y = 6x − 11

−2x − 3y = −7

• -2(-11) -3y= -7

• -2(6x-11) -3y = -7

• -2x -3(11) = -7

• -2x - 3(6x-11)= -7

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What variable do you eliminate?

4x + 8y = 20

−4x + 2y = −30

• X because they have opposite signs

• Y because they have opposite signs

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6