Algebra Test QuestionsDate: 1/25/96 at 19:26:10 From: DR MARK B VECCHIO Subject: algebra I am studying for exams and need some help solving some problems. 1. Find 3 consecutive integers such that the sum of the first and third is 84. 2. The length of a rectangle is 5 less than twice the width, the perimeter of the rectangle is 80; find the dimensions of the rectangle. 3. c + 2/5 = 3/7 4. 1/6 = a + 3/a-4 I would like to know how to work these out! Thanks - Middle school student Date: 1/27/96 at 21:22:10 From: Doctor Ken Subject: Re: algebra Hello! As DR MARK B VECCHIO wrote to Dr. Math, > >1. Find 3 consecutive integers such that the sum of the first and >third is 84. Try this: let x be the first number, x+1 be the second, and x+2 be the third. Then x+x+2 = 84. >2. The length of a rectangle is 5 less than twice the width, the >perimeter of the rectangle is 80; find the dimensions of the >rectangle. Translating into equations, we get l = 2w - 5 l + l + w + w = 80 >3. c + 2/5 = 3/7 The first step in solving this would be to move the 2/5 over to the right side, right? So you'd get c = 3/7 - 2/5. Then all you'd have to do is do the subtraction. >4. 1/6 = a + 3/a-4 What you want to do is get rid of all the fractions, right? Well, you've got a 6 on the bottom of one fraction, and an "a" on the bottom of another, so try multiplying through by 6, and then by a, and then you can either factor or use the quadratic formula. How fun! -Doctor Ken, The Geometry Forum |
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