MSA Quiz 1 Keep ALL SLOPE answers in

MSA Quiz #1 Keep ALL SLOPE answers in fraction form!

Math CC 7/8 – Dec. 12 Things Needed Today (TNT) q. Pencil/Math Notebook/Homework WS Math Notebook 1. Topic: Solving 2 Steps Equations 2. HW: WS- Solving 2 -Steps Equations & Combining Like Terms

What’s Happening? q HW Questions q. Warm Up q MSA- Solving 2 Steps Equations q. Begin HW?

Warm Up Combine Like Terms a) 4(x – 2) – 10 + 3 x 4 x – 8 – 10 + 3 x 7 x - 18 b) -2 x - 8(x -9) + 5 (x – 20) -2 x - 8 x +72 + 5 x – 100 -5 x - 28

Quick Review The equation is like a balance scale. What you do to one side of the equation must be done to the other side of the equation. What you DO to one side of the equation MUST be done to the other side , to keep it balance!

What is a Two-Step Equation? An equation that requires two steps to solve It takes 2 steps to solve an equation OR inequality that has more than one mathematical operation

Solving 2 Steps Equation Rules to Remember q. When solving an equation, the goal is to get the variable by itself. q. Addition and Subtraction are inverse operations. (opposites) q. Multiplication and Division are inverse operations. (opposites)

How to solve two-step equations q. Step 1 - Identify the variable q. Step 2 - Add/Subtract whole numbers so the #s are ALL on one side. ( DO IT TO BOTH SIDES OF THE = SIGN) q. Step 3 - Multiply /Divide to get the variable by itself q. Step 4 – ALWAYS check your work (substitute your solution into the original equation.

Other Ways to Solve 2 Steps Equations 1) “Undo” the operations in the reverse order of the order of operations. 2) This is called the work back-wards strategy 3) In order of operations we do multiplication or division first, then addition and subtraction. 4) When solving an equation we do the opposite!

Here we go…. . The problem contains addition (+) and multiplication ( • ). Which one do we undo 1 st? 3 x + 2 = 23 -2 -2 3 x = 21 3 3 x=7

Example The problem contains subtraction (-) and multiplication ( • ). Which one do we undo 1 st? -2 y – 7 = 3 +7 +7 -2 y= 10 -2 -2 y = -5

Example The problem contains addition (+) and multiplication( • ). Which one do we undo 1 st? -3 c + 9 = 3 -9 -9 -3 c = -6 -3 -3 c= 2

More Practice 8 x + 5 = 61 - 5 So to UNDO: What will you do 1 st? Hmmmmm…. -Subtract 5 then… -Divide by 8. 8 x = 56 Whatever we do on one side, we have to do on the other.

This problem has multiplication, so we need to divide (÷) now. Next Step 8 x = 56 8 8 x= 7 Whatever we do on one side, we have to do on the other.

More Practice -5 x + 3 = 38 -3 -3 What will you do 1 st? UNDO in reverse… -Subtract 3 -Divide by -5 -5 x = 35 Whatever we do on one side, we have to do on the other.

Next Step This problem has multiplication ( • ), so we need to divide (/) now. -5 x = 35 -5 -5 x = -7 Whatever we do on one side, we have to do on the other.

2 x + 4 = 10 -4 -4 2 x = __ __ 6 2 2 x =3 2(3) +4 = 10 6 + 4 = 10 10 = 10 Get the variable alone. Subtract 4 from both sides. +4 and -4 cancel out Divide both sides by 2 2 divided by 2 cancel to 1 Show your check. Finish your check.

3 m - 10 = 17 Get the variable alone. + 10 +10 __ 3 m = __ 27 3 3 m =9 3(9) – 10 = 17 27 – 10 = 17 17 = 17 Add 10 to both sides. +10 and -10 cancel out Divide both sides by 3 3 divided by 3 cancel to 1 Show your check. Finish your check.

x – 4 = 8 Get the variable 3 3 x (3 x 36 3 +4 +4 = 12 ) = 3 12 = 36 – 4=8 12 – 4 = 8 8=8 alone. Add 4 to both sides. + 4 and -4 cancel out. Multiply both sides by 3. 3 divided by 3 cancel to 1 Show your check. Finish your check.

x + 6 = 14 Get the 2 2 x (2 x 16 2 -6 -6 =8 ) =2 8 = 16 + 6 = 14 8 + 6 = 14 14 = 14 variable alone. Subtract 6 from both sides. + 6 and -6 cancel out. Multiply both sides by 2. 2 divided by 2 cancel to 1 Show your check. Finish your check.

More Fun Coming Your Way UNDO in Reverse… What will you do 1 st? + 9 = 40 Whatever we do on one side, we have to do on the other. - Add (+)9 - Multiply (*) by -4

Next Step • This problem has division (/), so we need to multiply (*) now. a = -160 Whatever we do on one side, we have to do on the other.

Math Fun What will you do 1 st? UNDO in reverse… - Multiply (*) by 3 - Add (+) 8 a - 8 = 12 Whatever we do on one side, we have to do on the other.

Next Step…. a - 8 = 12 +8 +8 a = 20 Whatever we do on one side, we have to do on the other.

More Problems Show ALL steps & work! 7 f + 5 = 40 f=5 t = 186 - 7 = 13 m = 100 = 90 + 8 = -12 y = -80

2 Step Subtract/Multiply Equation • 3 m - 10 = 17 Get the variable alone. +10 Add 10 to both sides. __ = 27 __ 3 m 3 3 m =9 3(9) – 10 =17 27 – 10 =17 17 =17 +10 and -10 cancel out Divide both sides by 3 3 divided by 3 cancel to 1 Show your check. Finish your check.

x + 6 = 14 Get the variable 2 -6 x 2( 2 x -6 =8 ) =2 8 = 16 16 2 + 6 = 14 8 + 6 = 14 14 = 14 alone. Subtract 6 from both sides. + 6 and -6 cancel out. Multiply both sides by 2. 2 divided by 2 cancels out Show your check. Finish your check.