# math

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The cross section of an attic is in the shape of an isosceles trapezoid. If the height of the attic is 9 feet, BC=12 feet, and AD=28 feet, find the length of line AB to the nearest foot.

The triangle of the trapezoid is triangle ABE and the bases are BC and AD.

Could you also give me a link about the theorems and postulates of a two column proof?

• math -

I assume BE is the height of the trapezoid.
then AE=8
and by Pythagoras
AB^2 = 64+81 = 145
AB = √145 = 12.042

• math -

Eat some wee wee you ain't you when you're hungry.

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