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Algebra/quadratic relations

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Question
A rectangle piece of tin 40 cm by 30 cm is to be made into an open box with a base of 900cm2 by cutting equal squares from the hour corners and then bending up the sides. Find, to the nearest tenth of  a centimetre the length of the side of the square cut from each corner.

Answer
The squares would have a side of length x, and there are two squares (one at each end)
on each side.  The area of the base is then (40-2x)(30-2x), and that is suppose to be 900.

Multiplying out the area gives 4x - 140x + 1200.
Setting that to 900 gives 4x - 140x + 1200 = 900.

Subtracting 900 from both sides gives 4x - 140x + 300 = 0.
Dividing the equation by 4 gives x - 35x + 75 = 0.

Putting this equation in Excel lets x be estimated to be 2.3,
so each square should be 2.3 x 2.3.

Algebra

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Scott A Wilson

Expertise

Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

Experience

I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

Publications
Documents at Boeing in assistance on the manufacturiing floor.

Education/Credentials
MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

Awards and Honors
Both my BS and MS degrees were given with honors.

Past/Present Clients
Students in a wide variety of areas since the 80's; over 1,000 of them have been in algebra.

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