Question 1153754: I need help on how to find the equation in quadratic word problems and my teacher doesn't teach very well. I am okay with most of the ways on how to use the quadratic formula and get standard form but I don't get how you find an equation using the information given in the word problem. I have tried asking for help and looking online but I still don't get it.
Question examples:
1) A rectangular piece of tin 40cm by 30cm is to be made into an open box with a base of 900cm^2 by cutting equal squares from the four corners and then bending up the sides. FInd the length of the side of the square cut from each corner.
2) Pete drove from Buffalo to Boston, a distance of 4000km. On the return trip, the speed was increased by 300km/h. If the total trip (There and back) took 13hours, what was the speed from montreal to San Fransico.
Answer by ikleyn(52781)   (Show Source):
You can put this solution on YOUR website! .
Problem 1)
After cutting the squares and then bending, the dimensions of the base of the box will be (40-2x) cm and (30-2x) cm,
where x is the side of the square.
It is the first and the major step in the solution.
Then the area of the base of the box is the product (40-2x)*(30-2x).
It should be equal to 900 cm^2, which gives you the equation
(40-2x)*(30-2x) = 900.
Next, you should simplify it; reach a quadratic equation in standard form, simplify and solve.
Problem 2)
Please read your post to ensure that part 2) is NONSENSE.
PLEASE AVOID POSTING nonsense to this forum.
I don't like it VERY MUCH.
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Also, NEVER post more than one problem/question per post.
It is the policy, the rule and the REQUIREMENT of this forum.
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