Trapezoid

Trapezoid questions on the ACT usually relate to the area of the shape or the internal angles of the shape. As a result, it’s worth knowing that the area formula for a trapezoid is:

And that a trapezoid has 360 degrees of internal angles inside of it.

Key points to remember for ACT trapezoid problems:

• Identify the bases: Always double-check which sides are the parallel bases of the trapezoid. 
• Perpendicular height: The height of a trapezoid must be perpendicular to both bases. 
• Formula application: Memorize the formula for the area of a trapezoid: Area = (1/2) * (Base1 + Base2) * Height. 
• Algebraic manipulation: Be prepared to solve for missing variables in the formula if necessary. 

• Be aware of special properties of isosceles trapezoids (equal leg lengths, diagonals of equal length).
• Pay close attention to units and ensure your final answer is in the correct unit.
• Sometimes you may need to use the Pythagorean theorem to find missing side lengths in a trapezoid.