Warmup 3/29 Substitution Method

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

• get x by itself

• get y by itself

• get either variable by itself in one equation

• add the equations together

Solve:
x = -3y - 17
2x + 3y = -7

• (1, -20)
• (3, 0)
• (-5, -2)
• (10 , -9)

4x - 5y = 21

x - 3y = 7

• (4, -1)

• (-4, -1)

• (-3, 2)

• (1, -3)

The solution (x, y) to a system of equations is the point where they...? 

• Run off the graph
• Don't touch
• Intersect
• Exist

Which equation is correctly using substitution for the system shown?

y = x + 6

y = -2x − 3

• x + 6 = -2x − 3

• y = x + 6 − 2x − 3

Put the steps in the right order.

• Isolate one of the variables.

• Solve for second variable

• Substitute the number found into a starting equation and solve for first variable.

• Substitute this for the first variable into the other equation.

Which word matches this definition?

Multiply all terms inside parenthesis by term outside parenthesis

• Systems of Equations

• Combine Like Terms

• Distributive Property

• Substitution

Which word matches this definition?

A group of equations using the same variables

• Systems of Equations

• Combine Like Terms

• Distributive Property

• Substitution

Which word matches this definition?

Add or subtract similar terms

• Isolate a Variable

• Combine Like Terms

• Distributive Property

• Substitution

Which word matches this definition?

Replacing a variable with what it is equal to

• Isolate a Variable

• Combine Like Terms

• Distributive Property

• Substitution