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ACT Math: Geometry

SAT Question of the Day

The SAT question of the day is a Sentence Completion Question that has already been addressed on this blog: click here to see an explanation.

ACT Question of the Day

The ACT question of the day is a geometry question that tests your knowledge of triangles.

This question asks you to find the area of triangle ABC.  Remember the formula for the area of a triangle?  It is one half of the base times the height.  

Gather all of the information that you know about this triangle.  The problem tells you that sides AB and AC are congruent; they are the same length.  That tells you that you have an isosceles triangle, but you do not know the length of either of these sides.  You also know that side BC is 10 units long.

Think about the formula for the area of the triangle.  You must have two measurements in order to use it.  You only have one measurement.  You have the base of this triangle, but no way to find the height; the other two sides could both be very short, or they could both be very long.  The height could be an infinite variety of lengths.  You cannot solve this problem.  Look down at your answer choices. 

The correct answer is (K).  The answer cannot be determined from the given information.

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