MEDALLL

Sarah wants to hang a mirror in her room. The mirror and frame must have an area of 15 square feet. The mirror is 3 feet wide and 4 feet long. Which quadratic equation can be used to determine the thickness of the frame, x?

http://learn.flvs.net/webdav/assessment_images/educator_algebra1_v10/09_00_64.jpg

Answers:

3x^2 + 14x - 2 = 0

4x^2 + 14x - 3 = 0

x^2 + 12x - 14 = 0

2x^2 + 7x - 14 = 0

Question

MEDALLL

Sarah wants to hang a mirror in her room. The mirror and frame must have an area of 15 square feet. The mirror is 3 feet wide and 4 feet long. Which quadratic equation can be used to determine the thickness of the frame, x?

http://learn.flvs.net/webdav/assessment_images/educator_algebra1_v10/09_00_64.jpg

Answers:

3x^2 + 14x - 2 = 0

 4x^2 + 14x - 3 = 0

 x^2 + 12x - 14 = 0

 2x^2 + 7x - 14 = 0

imstuck · Answer

This is assuming that the frame's thickness is a constant all the way around the frame...

imstuck · Answer

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imstuck · Answer

Setting up a quadratic equation for this for area...the area is equal to the length times the width.  Since you don't know what the frame is, the new length is 3 + x, and the new width is 4 + x.  Those would be multiplied together to = 15.  So it looks like this:

imstuck · Answer

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