Solving Systems Using Substitution Easy

Solve the system of equations using substitution:

-4x + 4y = 8

y = -2x - 10

• (-4, -2)

• (12, -34)

• (4, -18)

• (-2, -6)

• (-4, 6)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system of equations using substitution.

x=​ (a)  

y=​ ​ (b)  

• 3

• -2

• 1

• 0

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve for x and y using the substitution method. 5x + 3y = 7 y = 4

• (4,1)

• (4,-1)

• (1,4)

• (-1,4)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

solve by substitution: y=3x+14

y=-4x

• (2, 8)

• (-2, -6)

• (-2, 8)

• (-2, -4)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve for x and y (Use Substitution)

y = 2x + 1

y = 4x - 1

• (1,3)

• (-1,-3)

• (-1,3)

• (3,1)

• (1,1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the solution to this system?
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

Solve the following systems of equations using substitution:

x = 6

y = 2x - 3

• (6, 6)

• (6, 9)

• (9, 6)

• (9, 9)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

x = y - 2
4x + y = 2

• (2,0)

• (0,2)

• (0, -2)

• (-2,0)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Why does substitution help us solve a system of equations?

• It changes one variable to an expression using the other variable, so we can solve an equation that only has one variable at a time.

• It creates a problem with fewer steps.

• It puts both equations in slope-intercept form for easy graphing.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

TRUE or FALSE:

When both equations have the same variable isolated

(both y = or both x = ),

substituting the first into the second ends up looking like

you just set the two equal to each other.

• TRUE

• FALSE

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6