Name_____________________________________________________ Christmas Break Assignment Period _____ Algebra II Equations Packet This assignment is to be completed by you over Christmas break. You are to record your answers on this sheet of paper. All of your work must be written neatly in the packet. If your work is not shown for every problem, you will receive no credit. This assignment will be counted as a quiz and you will also take an exam on this material after the break. This assignment is due on Monday January 3, 2011 in class. This means you must bring it to class, not leave it at home or in your locker. If it is not in class on Monday, you will lose points for each day it is late. If you need to ask any questions, please feel free to e-mail me. 1. ______________ 2. ______________ 3. ______________ 4. ______________ 5. ______________ 6. ______________ 7. ______________ 8. ______________ 9. ______________ 10. ______________ 11. ______________ 12. ______________ 13. ______________ 14. ______________ 15. ______________ 16. ______________ 17. ______________ 18. ______________ 19. ______________ 20. ______________ 21. ______________ 22. ______________ 23. ______________ 24. ______________ 25. ______________ 26. ______________ 27. ______________ 28. ______________ 29. ______________ 30. ______________ Equations 1. Absolute Value Equations To solve an absolute value equation, you must: 1. Isolate the Absolute Value 2. Split into two equations – Positive and Negative (one side equals the positive value and the other side equals the negative value) **when you have a binomial, use parenthesis and remember to distribute 3. Solve each equation for x 4. Check both answers in the original problem. Examples: Solve |x + 6| - 18 = 2x + 18 + 18 |x + 6| = 2x + 18 2 + 3|x + 5| = 14 -2 -2 3|x + 5| = 12 3 3 |x + 5| = 4 x+5=4 x = -1 x + 5 = -4 (negate) x = -9 Now check both answers 2 + 3|x + 5| = 14 2 + 3|x + 5| = 14 2 + 3|(-1) + 5| = 14 2 + 3|(-9) + 5| = 14 2 + 3|4| = 14 2 + 3|-4| =14 2 + 3(4) = 14 2 + 3(4) = 14 2 + 12 = 14 2 + 12 = 14 14 = 14 14 = 14 √ x = {-9, -1} √ x + 6 = (2x + 18) x + 6 = 2x + 18 -x -x 6 = x + 18 -18 -18 -12 = x x + 6 = -(2x + 18) negate x + 6 = -2x -18 -x -x 6 = -3x – 18 +18 +18 24 = -3x -3 -3 -8 = x Now check both answers |x + 6| - 18 = 2x |x + 6| - 18 = 2x |(-12) + 6| - 18 = 2(-12) |(-8) + 6| - 18 = 2(-8) |-6| - 18 = -24 |-2| - 18 = -16 (6) – 18 = -24 (2) – 18 = -16 -12 ≠ -24 -16 = -16 x x = {-8} √ -12 is extraneous, so x ≠ -12 Practice: 1. | x – 1| = 4 Check 1 Check 2 2. |-6 + a | = 9 3. 2|2x – 4| = 86 Check 1 Check 2 4. |-5x| + 4 = -11 Check1 Check 1 Check 2 Check 2 |π₯+4| Check 1 Check 2 6. -4|b – 2|-9 = -37 Check 1 7. |x + 6| = 2x Check 1 Check 2 8. |2x + 12| = 7x – 3 Check 1 9. |2x – 6| - x = 3 Check 1 Check 2 10. |4x + 5| + 3x = 10 5. 10 =1 Check 1 Check 2 Check 2 Check 2 2. Radical Equations To solve a radical equation: 1. 2. 3. 4. 5. Isolate the radical on one side of the equation Square or both sides of the equation Solve the remaining equation for x Check answer in the original problem. (Extraneous Roots) Model Problem 1: Solve: 3 = √π₯ − 1 2 (3)2 = (√π₯ − 1) 9=x–1 10 = x Check: x = 10 3 = √π₯ − 1 3 = √10 − 1 3 = √9 3 = 3 √ Check Model Problem 2: Solve: √3π₯ + 1 − 1 = π₯ − 4 √3π₯ + 1 = π₯ − 3 2 (√3π₯ + 1) = (π₯ − 3)2 3x + 1 = x2 – 6x + 8 0 = x2 – 9x + 8 0 = (x – 8) (x – 1) (x – 8) = 0 (x – 1) = 0 x=8 x=1 Check: x = 8 √3π₯ + 1 − 1 = π₯ − 4 √3(8) + 1 − 1 = 8 − 4 √24 + 1 − 1 = 4 √25 − 1 = 4 5–1=4 4 = 4 √ check Practice: Solve each radical equation and check. 11. √−8 − 2π₯ = 4 Check x=1 √3π₯ + 1 − 1 = π₯ − 4 √3(1) + 1 − 1 = 1 − 4 √3 + 1 − 1 = −3 √4 − 1 = −3 2 – 1 = -3 -1 = -3 x οReject! 12. √π₯ − 4 = −12 Check 13. √2π₯ − 6 = √3π₯ − 14 Check (hint: If a radical is on both sides of the equation, square both sides, then solve) 14. √π₯ + 1 + 2 = 4 Check 15. √8π₯ = π₯ Check 16. π₯ = 4 + √2π₯ − 8 Check 17. π¦ = √6π¦ + 16 Check 18. √2π₯ − 7 = π₯ − 3 Check 19. −3 = √37 − 3π₯ − π₯ Check 20. √3π₯ − 8 + 1 = 3 Check 3. Solving Equations with Fractional Exponents To solve you must: 1. Isolate the expression containing the exponent (the base) 2. Raise both sides of the equation to the reciprocal of the exponent (Give both sides a new exponent: the reciprocal) 3. Solve for x 4. Check in the original 3 Example 1: Solve 54 = 2π₯ 2 REMEMBER: 3 2 54 = 2π₯ 2 2 Fractional Exponents represent ππππΈπ radicals. π πππ 3 27 = π₯ 2 2 3 2 2 (27)3 = ( π₯ 2 )3 9=x 2 3 273 = ( √27 ) = 32 = 9 −1 EXAMPLE 2: Solve: 5 = 3 + 4π 6 a is the base! We must isolate it. −1 6 −1 6 2 = 4π 1 2 = π Raise each side to the reciprocal power The reciprocal of 1 −6 ( ) 2 =π 26 = a 64 = a −1 6 is -6 Negative exponents: flip the base, exponent becomes positive 5 EXAMPLE 3: Solve: -3 + (8 − 2π₯)4 = 29 The base is (8 – 2x)! Isolate! 5 (8 − 2π₯)4 = 32 4 5 5 4 Reciprocal Power! 4 ((8 − 2π₯) ) = (32)5 5 8 − 2π₯ = ( √32)4 8 − 2π₯ = 16 −2π₯ = 8 π₯ = −4 Now, solve for x! Practice: 3 −3 21. π₯ 4 + 6 = 33 22. π₯ 2 = 1 1 729 3 23. 11 = 2π₯ 2 − 3 24. (π − 27)2 = 64 3 25. 26 = -1 + (27π₯)4 5 26. 3125= (−1 – 18x)3 −3 27. 4π 4 + 20 = 3 21 28. -54 = 10- (x – 10)2 2 5 29. -5126 = -6 - 5(3π₯ + 22)3 3 30. 3646 = 1 + 5(4π₯ + 17)2