Solving Equations in Two Variables

When solving an equation, our goal is to:

• add all the numbers together.

• use a calculator.

• eat lunch.

• isolate the variable to solve.

In order to solve an equation, we must get variables on one side of an equation, and constants on the opposite side.

• False

• True

The objective when solving an equation is to....

• isolate the variable.

• check the solution.

• guess and check.

• Combine Like Terms.

How do you know when it is "no solution"?

• The constants are different on either side of the equal sign.

• The constants are the same on either side of the equal sign.

• The variables all cancel out.

• Both sides are the same

Solve for y:
2x + 2y = 6

• y = - x + 3

• y = x + 3

• y = 2x +6

• y = - 2x + 6

5x - y = 16

• -y = 5x + 16

• y = 5x + 16

• x = 5y - 16

• y = 5x - 16

-16x=2y-10

• 8x+y=5

• -16x-2y=10

• 16x+2y=-10

• 8x-y=-5

Rewrite the equation in STANDARD form.

-16x=2y-10

• 8x+y=5

• -16x-2y=10

• 16x+2y=-10

• 8x-y=-5

-4=-x+2y 

•  x-2y=4

• x-2y=-4 

• 4=x-2y 

• x+2y=4 

The solution of equation x-2y = 4 is:

• (0,2)

• (2,0)

• (4,0)

• (1,1