Gmat Prep 2- Triangle Question

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Gmat Prep 2- Triangle Question

by charmingirl8 » Wed Sep 05, 2007 5:14 pm
Can anyone help with this question? Thanks!
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by ri2007 » Wed Sep 05, 2007 5:21 pm
You have been given the measures of the sides of the two triangles on the side, you also know that they are right angle triangles. With this you can fnd that the measure of the sides of the triangle with one angle X and the other is 5 & 5. So it is a isoceleus triangle. So the two base angles are 55.
Angle X = 180 - (55 +55)

= 70

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by agps » Wed Sep 05, 2007 11:21 pm
the triangle to the left is a 3-4-5 special triangle.
the triangle to the right is a 5-12-13 special triangle.
since this is a isosceles triangle (can't be equilateral because of the angle 55º), the other angle that is not x is also 55º.
sum of angles of triangle is 180, so x=180-55-55 = 70.

this requires only 1 calculation " x=180-55-55", if you know the triangle properties and the special triangle values, always look for them, gmat testers seem to love them to death :twisted: