PREC11 Unit1 notes

# Answer the width of the plot is 10 m and the length

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Unformatted text preview: king you to find. example: 40 m of wire fencing will be used to make a rectangular plot that encloses a play area for your pet dog. A wall of your house is to serve as one side of the plot. What dimensions would give a maximum plot area? 1) Define variables and write expressions. • The area must be maximized. • We need an area function that is quadratic. The area of a rectangle is the product of its width and length. Write expressions for the dimensions of the plot. house plot Let A represent the plot's area in square metres. Let x represent the length of the plot's side perpendicular to the house's wall in metres. Then 40 − 2x represents the length of the plot's side parallel to the house's wall in metres. 2) Write the quadratic area function. 3) Solve the equation; write it in vertex form. A = x (40 − 2x) A = 40x − 2x2 A = −2x2 + 40x A = −2[x2 − 20x 2 A = −2[x − 20x + 100 − 100] A = −2[(x − 10)2 − 100] A = −2(x − 10)2 − 2(−100) A = −2(x − 10)2 + 200 The vertex is (10,200) and...
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## This document was uploaded on 02/16/2014 for the course MATH Pre-Calcul at Holy Cross Regional High School.

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