Solving Systems of Equations Review

What is the solution to the system of equations?

4x-y=3

3x+y=4

(​ (a)   ,​ (b)   )

• 1

• 2

• 3

• 4

• 5

• 6

• 7

• 8

• 9

• 0

Put the steps for solving by SUBSTITUTION in order:

• Plug that number into the other equation

• Solve for the first variable

• Solve one equation for x or y

• Solve for the second variable

• Plug the resulting expression into the other equation

In this system

x+3y=9

4x-2y=-6

it'll be easiest to start by solving the first equation for x.

The result of doing so is x=​9-3y.

Fill in the blanks to plug that expression in and solve for y:

4(​9-3y)-2​y =-6

36-​12y-2y=​-6

36-​14y =-6

-14y=​ (a)  

y=​ (b)  

• -42

• 3

• 30

• -3

In this system

x+3y=9

4x-2y=-6

we have figured out that x=9-3y, and y=3.

Complete the steps to solve for x:

x=9-3(​ (a)   )

x=9-​ (b)  

x=​ (c)  

The solution to the system is (​ (d)   ,​ (e)   ).

• 3

• 9

• 0

• y

• x

• y=3

• 3y

• -9

• 18

Enter the x coordinate of the solution to this system of equations.

HINT: Make sure both equations are in (x + y = #) form. Then do the shortcut.

Mathematical Equivalence

ON

What is the x coordinate of the solution to this system of equations? HINT: Graph and use nSolve. Menu 64.

Mathematical Equivalence

ON

Enter the x coordinate of the solution to this system of equations. HINT: Make sure both equations are in (y=mx+b) form. Then do the shortcut with DESMOS

Mathematical Equivalence

ON

(a)  

• A

• B

• C

• D

Put the steps for solving by ELIMINATION in order:

• Plug that number into either original equation and solve for the other variable

• Subtract the equations to eliminate one variable

• Solve for the remaining variable

• Multiply one or both equations by a number to get common but opposite coefficients

• Make sure the equations are lined up