Solving Systems with Substitution in Slope Intercept Form

The first step in solving using the substitution method is __________.

• get x by itself

• get y by itself

• get either variable by itself

• add the equations together

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the correct first step in solving this system by substitution?

• -7(2y+11) - 2y = -13

• -7x -2(2y +11) = -13

• 2y+11-2y = -13

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve with substitution

x = -3y - 8

x - 2y = -3

• (5, -1)

• (-5, 1)

• (-5,-1)

• (1,-5)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the best method do you use?

x = 6y − 11

−2x − 3y = −7

• Graphing, because they are both in slope-intercept form

• Substitution because a variable is isolated (solved for)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the solution to this system? Solve by substitution.
y= 4x + 3
2x - 3y = 21

• (3,-9)

• (-3,-9)

• (-3,9)

• (0,1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• A
• B
• C
• D

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

solve by substitution: y=3x+14
y=-4x

• y=3

• y=1

• y= - 2

• y=4

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system by substitution

3x - y = 4

x + 2y = 6

• (-2, 2)

• (2, -2)

• (2, 2)

• (-2, -2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve with substitution:

y = -2x + 18

y = 8

• (5, 8)

• (-5, 8)

• (2, 8)

• (-2, 8)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve using substitution:

y = -6x + 5

-2x + y = 5

• (-3, -6)

• (-6, 3)

• (0, 5)

• (-3, 5)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6