45 x 2

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45 45

Since the angles of a triangle add up to 180 degrees, the angle at the top has to be 90 degrees. The top angle can also be described as two 45 degree angles to a vertical line bisecting the house to the middle of the floor. In other words, the two right triangles are mirror images, each with a base of 10.5 feet. Since the angle at the top of each right triangle is also 45 degrees, the height must also be 10.5 feet.

It's a rather short roof for an A-frame house. Normally, A frames have about a 60 degree angle at the base. Are you sure the vertex at the peak isn't 45 degrees, rather than the base angles?

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/__|__.

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45 45

Since the angles of a triangle add up to 180 degrees, the angle at the top has to be 90 degrees. The top angle can also be described as two 45 degree angles to a vertical line bisecting the house to the middle of the floor. In other words, the two right triangles are mirror images, each with a base of 10.5 feet. Since the angle at the top of each right triangle is also 45 degrees, the height must also be 10.5 feet.

It's a rather short roof for an A-frame house. Normally, A frames have about a 60 degree angle at the base. Are you sure the vertex at the peak isn't 45 degrees, rather than the base angles?