right angle triangle
<img width="125" height="100" src="https://scienceres-edcp-educ.sites.olt.ubc.ca/files/2013/04/sec_math_tri_unitCircle-125x100.jpg" class="attachment-post-thumbnail size-post-thumbnail wp-post-image" alt="" decoding="async" />
The Unit Circle
<img width="125" height="100" src="https://scienceres-edcp-educ.sites.olt.ubc.ca/files/2013/04/sec_math_tri_454590-125x100.jpg" class="attachment-post-thumbnail size-post-thumbnail wp-post-image" alt="" decoding="async" loading="lazy" />
45-45-90 Triangles
<img width="125" height="100" src="https://scienceres-edcp-educ.sites.olt.ubc.ca/files/2013/04/sec_math_tri_306090-125x100.jpg" class="attachment-post-thumbnail size-post-thumbnail wp-post-image" alt="" decoding="async" loading="lazy" />