The winter sky has some brightly lit star patterns visible this month, including a triangle featuring Mars at one of its points, making it worthwhile to brave the winter temperatures for stargazing.

Image caption, For a right-angled triangle, the base and the perpendicular height are the two sides that are at right angles. The perpendicular height is the perpendicular measurement that gives ...

Big Idea – We can describe, measure, and compare spatial relationships. to build on students' knowledge of triangle and to develop students' reasoning with properties of triangle to develop students' ...