SOLUTION: Would someone show me step by step how to figure out this word problem? Thank you The length of a rectangle is 1cm more than 5 times its width. If the area of the rectangle is 79

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Question 88165: Would someone show me step by step how to figure out this word problem? Thank you
The length of a rectangle is 1cm more than 5 times its width. If the area of the rectangle is 79 cm^2, find the dimensions of the rectangle to the nearest thousandth.
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
The length of a rectangle is 1cm more than 5 times its width. If the area of the rectangle is 79 cm^2, find the dimensions of the rectangle to the nearest thousandth.
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Let x = width of the rectangle
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It says "the length of a rectangle is 1cm more than 5 times its width" Therefore:
(5x + 1) = the length
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If the area of the rectangle is 79 cm^2,
L * W = 79
Which is:
x(5x+1) = 79; substituted x for width and (x+1) for length
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5x^2 + x = 79; multiplied what was inside the brackets
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5x^2 + x - 79; subtracted 79 from both sides, gives us a quadratic equation
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This equation has to be solved by the quadratic formula a^2 + bx + c = y
in our equation: a = 5; b = 1; c =-79

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;

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; minus a minus is a plus
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WE are only interested in the positive solution here:
; found the square root of 1581
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x = 3.876 is the width, Then the length = (5*3.876) + 1 = 20.38
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Check solutions:
3.876 * 20.38 = 78.99 ~ 79
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Was this enough steps to put on the right track here?