An open box is made from a 30​-cm by 60​-cm piece of tin by cutting a square from each corner and folding up the edges. The area of the resulting base is 1144 cm2. What is the length of the sides of the​ squares?

Respuesta :

Answer:

  4 cm

Step-by-step explanation:

After the cut of length x from each corner, the size of the base will be ...

  (30 -2x) by (60 -2x)

You want to find x such that the product of these dimensions is 1144.

  (30 -2x)(60 -2x) = 1144

  (15 -x)(30 -x) = 286 . . . . . . divide by 4

  x^2 -45x +450 = 286 . . . . eliminate parentheses

  x^2 -45x +164 = 0 . . . . . . . subtract 286

  (x -4)(x -41) = 0 . . . . . . . . . . factor

The solution that is less than 15 cm is x = 4.

The sides of the squares are 4 cm.

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