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Solving Rational Equations. MM1A3d Solve simple rational equations that result in linear equations or quadratic equations with a leading coefficient of 1. Solving Rational Equations. Rational Equation Contains Rational expressions 6 = x x+5 6. Solving Rational Equations Cross Products.
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Solving Rational Equations MM1A3d Solve simple rational equations that result in linear equations or quadratic equations with a leading coefficient of 1.
Solving Rational Equations Rational Equation Contains Rational expressions 6 = x x+5 6
Solving Rational EquationsCross Products 6 = x 6(6)=x(x+5) 1. Cross multiply x+5 6 36=x2+5x 0=x2+5x-36 2. set quadratics equal to zero 0=(x+9)(x-4) 3.factor x+9=0 x-4=0 4.solve each for x=-9 x=4 zero
Solving Rational EquationsCross Products You try: -12 = x-14 x 4 • Cross multiply • Distribute • Factor • Set to zero if quadratic • Solve each set of parentheses. -12(4) = x(x-14) -48 = x2-14x0= x2-14x+48 0=(x-6)(x-8) X-6=0 x-8=0 X=6 x=8
Solving Rational EquationsMultiply by the LCD If there is more than one expression on a side of the equation, you cannot cross multiply. 3x - 5 = 5 x+5 2 x+5 See how there are two expressions on the left side.
Solving Rational EquationsMultiply by the LCD 3x - 5 = 5 LCD (x+5)(2) x+5 2 x+5 3x(x+5)(2) -5(x+5)(2) = 5(x+5)(2) (x+5) (2) (x+5) 3x(2)-5(x+5)=5(2) 6x-5x-25=10 X-25=10 X=35 Multiply everything by the entire LCD Cancel out like terms between top and bottom Expand-distribute Combine like terms Solve
Solving Rational EquationsMultiply by the LCD Try one- x + 1 = -7 X+10 5 x+10 Multiply everything by the entire LCD Cancel out like terms between top and bottom Expand-distribute Combine like terms Solve LCD 5(x+10) x(5)+x+10 = -7(5) 6x+10 = -35 6x = -45 x = - 15/2 or -7.5
Solving Rational EquationsFactor First Sometimes you have to factor the bottom first. 4 + 1 = 14 x-4 x2+x-20 (x-4)(x+5) Now work with a common denominator
Solving Rational Equations Project Rational Search Materials: Laptops Instructions: Go to at least three of the websites listed. Take notes on the presentations. Make sure your notes include at least three examples of problems worked out. Write a review of the websites by ranking them from 1 to 3 with 3 being the most helpful. Tell why you ranked them as you did. Find two more web based resources on the lesson and include them on your sheet to turn in.
Rational Search Sites http://www2.nemcc.edu/RHawkins/alglessons/solve_rational_equations.ppt http://teachers.henrico.k12.va.us/math/hcpsalgebra2/9-5.htm http://math.lhs.lusd.org/Algebra%201%20PowerPoint%20Lessons/Chapter%2010/lesson%2010.6_Solving_Rational_Equations.ppt http://www.klvx.org/DocumentView.asp?DID=182 http://www.mathslideshow.com/Alg1PH/Lesson10-6/index.htm http://www.scribd.com/doc/9012673/Rational-Expression-Power-Point
Solving Rational Equations Homework Page 178 (1-15)