Test your knowledge of taxicab geometry, triangular numbers, the golden ratio and more.

We spent forever arguing about the brain teaser that asks: How many triangles do you see? Here, mathematicians reveal the real answer. See if you’re right.

Yet another viral math equation is taking over the internet. This time, it's a pink triangle within a square that has people scratching their heads. Can you solve it?

Likewise, for the third side of the triangle, there are four lines left to choose from. Thus, the total number of ways you can choose the sides of the triangle equals 6 × 5 × 4, or 120. Clearly ...

DETROIT (AP)—Jackie Bredenberg knows her way around an isosceles triangle, a parallelogram and anything else in the mathematics stratosphere. So much so, she is only the second female to win ...

On the video, the rapper known as 2 Pi reels off rhymes as teenagers in classrooms and hallways sway and bop to the music. It's upbeat. It's catchy. It's . . . math. We solve triangles one by one ...

The Museum of Math flipped this idea around — if the lengths of the sides of a triangle, like the Flatiron building, satisfy the Pythagorean theorem, then the triangle must be a right triangle.

Jackie Bredenberg knows her way around an isosceles triangle, a parallelogram and anything else in the mathematics stratosphere. So much so, she is only the second female to win Gold #1 ...