Lesson solving two step equations when -x = #

two step equations

1. Solving two-step equations Focus: When – x = #

2. Let’s review the steps … 5 – x = 9 Step 1 : Draw a line down the middle of the equation through the equal sign to divide the equation into 2 equal sides. 5 – x = 9 This is to remind us that whatever we do to one side, we must also do to the other. Keep it balanced!

3. Let’s review the steps … Step 2 : Undo addition and subtraction (by adding the opposite) to zero out the number on the side with the variable. 5 – x = 9 Step 3 : Simplify -5 -5 and bring down – x = 4 remaining terms – 1 ∙ x = 4 Be careful not to drop the sign in front of x.

4. Let’s review the steps … Step 4 : Now undo multiplication by dividing by –1. – 1 x = 4 – 1 –1 Step 5 : Simplify x = – 4 Your answer is x = – 4 *** And now, for the most important step …

5. ALWAYS Check your Answer …. Step 6 : 5 – x = 9 5 – ( -4 ) = 9 Substitute your 5 + 4 = 9 answer in for x 9 = 9 √ and simplify.

6. Now Try These … Solve the following Two-Step Equations and message your answers to Mrs. Brinson. 7 – x = 5 -2 – x = 4 -x + 9 = 11 18 – x = -2 -3 – x = -7