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Please help me solve

Please help me solve-example-1

1 Answer

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if the area of a rectangle is width time length, then we have all of the info we need.

the width is 6 less than 3 times the length. let the length be x and put your words into math! 6 less is -6. 3 times a number is 3x, so width=3x-6.

so we have area=l×w which becomes x×(3x-6)=105

solve

x(3x - 6) = 105 \\ 3 {x}^(2) - 6x = 105 \\ 3( {x}^(2) - 2x) = 105 \\ (1)/(3) * 3( {x }^(2) - 2x) = 105 * (1)/(3) \\ {x}^(2) - 2x = 35 \\ {x}^(2) - 2x - 35 = 0
factor and solve!

you will get one positive and one negative. pick the positive since lengths cannot be negative
User Harry Geo
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