Notes: SRT.6a Slope Ratio of Angles
Learning Target
SRT.6a I can use proportional sides of similar, right triangles to compute the sloperatio of acute angles and I can use the tangent function to solve for the legs of right triangles.
All Acute Angles have a Slope Ratio
The slope ratio of an acute angle is the relationship of a rise to a run. The ratio can be calculated many ways, but it will always be the same ratio for a specific angle, no matter its orientation or size. The rise will always be perpendicular to the run. The rise is the perpendicular distance opposite the specific angle. The run is measured along either side of the angle.
The interactive diagram / tool below will help you visualize the slope ratio.
Slope Ratio of specific angles
Find the slope ratio of an 11° angle
1. Set the measure of angle AOC to 11°, using the blue dot on the outside of the protractor. 2. Check the Slope Ratio from side HG and side HF. Try to count the number of squares in the rise and the run in from each side. 3. Enter the ratio: rise over the run from side HG, and the ratio: rise over run from side HF.