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| Question 183953This question is from textbook Glencoe McGraw-Hill: Algebra 2
 :  Hi, I hope I am submitting this problem under the right section, the chapter I'm currently studying has asymptotes so..
 Haha, I've tried this problem so many ways! I feel that the mistake is right under my nose, but I still can't seem to find it. the dashes are fractions.
 4/z-2 - z+6/z+1 = 1
 I go to a private school, but I am currently being homeschooled for a couple weeks. My teacher wanted us to solve this problem by clearing the fractions.
 Here's my most "unjumbled" work:
 *original problem*
 LCD: (z-2)(z+1)
 (z-2)(z+1)/ 1  times 4/(z-2) minus (z-2)(z+1)/1 times (z+6)/(z+1) = (z-2)(z+1)/1 times 1.
 4z+4-(z-2)(z+6)=(z-2)(z+1)
 4z+4-z^2+6z-2z-12= z^2+z-2z-2
 4z+4-z^2+4z-12 = z^2-z-2
 -z^2+8z-8 = z^2-z-2
 eliminate -z^2+8z-8 on the left side, do the same to the right side like...
 0 = z^2-z-2
 +z^2-8z-8
 _______________  equals
 0 = 2z^2-9z-10
 not factorable, so I used quadratic formula
 a=2, b=-9, c=-10
 quadratic formula: [-b (+ or -) sq. root of: b^2 - 4ac] divided by 2a
 =[9 (+ or -) sq. root of: (-9)^2 - 4(2)(-10)] all divided by 4.
 = [ 9 (+ or -) sq. root of: 161] all divided by 4.
 my textbook says that the correct answer should be:
 [ 1 (+ or -) sq. root of: 145] all divided by 4.
 Mmm.. hopefully this is readable. Please help, it's driving me bonkers! Thanks!
 This question is from textbook Glencoe McGraw-Hill: Algebra 2
 
 Answer by edjones(8007)
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