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Do Now 10/27/09 Take out HW from last night. Punchline worksheets #43 & #44 Copy HW in your planner. Text p. 127, #12-18 even, #22-30 evens, #33 Quiz sections 3.1 & 3.2 Thursday In your notebook, simplify the expressions below. -2a – 3 + 4a + 8 -4a – 3(a + 8) -3(x + 4) Homework Punchline worksheets #43-44 “Books Never Written” JUSTIN HALE BUCK L UPSON OWEN E LEVIN “Did You Hear About…” THE GUY WHO INVESTED IN FEATHERS BECAUSE HE HEARD THAT THE STOCK MARKET WAS GOING DOWN Objective SWBAT solve multi-step equations using algebra Remember this… -3(x + 4) = -3(x) + (-3)(4) = -3x + (-12) -2a – 3 + 4a + 8 -2a + 4a + (-3) + 8 = 2a + 5 Remember this… -4a – 3(a + 8) -4a +(-3)(a + 8) -4a + (-3a) + (-24) -7a + (-24) Equation mathematical sentence with an equal sign Like a scale, both sides must be EQUAL in order to be balanced. Section 3.2 “Solving a Multi-Step Equation” How can you get the “unknown” by itself? 8x - 3x - 10 = 20 Solving Multi-Step Equations STEP 1STEP 2STEP 3STEP 4STEP 5STEP 6- Combine like terms. “Undo” addition and/or subtraction. “Undo” multiplication and/or division. Solve for the variable. Check your work. Solving Multi-Step Equations… Isolate the variable! Get ‘x’ by itself. 8x – 3x – 10 = 20 5x – 10 = 20 Combine like terms. 5x – 10 + 10 = 20 + 10 Add 10 to each side. 5x = 30 Simplify. 5x = 30 5 5 Divide each side by 5. x=6 Simplify. Check Your Work! 8x – 3x – 10 = 20 x =6 8(6) – 3(6) – 10 = 20 Are both sides equal? Solving a Multi-Step Equation Solving Multi-Step Equations STEP 1 - Distributive Property STEP 2- Combine like terms. STEP 3- “Undo” addition and/or subtraction. STEP 4- “Undo” multiplication and/or division. STEP 5- Solve for the variable. STEP 6- Check your work. Solving Multi-Step Equations Using the Distributive Property… 6x – 2(x – 5) = 46 Distributive property. 6x – 2x + 10 = 46 Combine like terms. 4x + 10 = 46 4x + 10 – 10 = 46 – 10 4x = 36 4x 36 = 4 4 x= 9 Subtract 10 from each side. Simplify. Divide each side by 4. Simplify. Check Your Work! 6x – 2(x – 5) = 46 x =9 6(9) – 2(9 – 5) = 46 Are both sides equal? Guided Practice 1) 6x – 2x + 11 = -5 4x + 11 = -5 4x = -16 x = -4 2) p – 17p – 6 = -38 -16p – 6 = -38 -16p = -32 p=2 Guided Practice 6x – 2(x + 11) = -6 6x + (-2x) + (-22) = -6 4x + (-22) = -6 4x = 16 x=4 Guided Practice 27 = 3c – 3(6 – 2c) 27 = 3c + (-18) + 6c 27 = 9c + (-18) 45 = 9c 5=c Homework Text p. 127, #12-18 even, #22-30 evens, #33