SSAT Middle Level
Quantitative (Math)

Finding the Length of the Third Side in a Triangle

Medium Geometry And Measurement Triangles And Polygons

A triangle has two sides of equal length, measuring 7 cm each, and the included angle between them is 60 degrees. Determine the length of the third side of the triangle using the Law of Cosines.

Recall that the Law of Cosines states that for any triangle with sides $a$, $b$, and $c$, and angle $C$ opposite side $c$, the following formula holds: $$c^2 = a^2 + b^2 - 2ab imes ext{cos}(C)$$.

Hint

Submitted4.4K
Correct3.3K
% Correct75%