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The Wheelchair Ramp

Part of the Right-Triangle Trigonometry section of Coddy's Trigonometry journey. Lesson 42 of 46.

A café wants a ramp to its door, which is 0.7 m above the pavement. The builder has room for a ramp 9 m long. US rules allow at most a rise of 1 for every 12 along the ground, an angle of about 4.76°. Does a 9 m ramp stay within that?

Challenge

A ramp 9 m long rises 0.7 m. Find the angle θ it makes with the ground, in degrees, to two decimal places, and compare it with the 4.76° limit. Then press Check.

Try it yourself

$Use the figure to find theta$

Use the figure to find theta

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Right-Triangle Trigonometry

1Measuring With an Angle

How Tall Is the Tree?Naming the Sides The Tangent Ratio

4Finding the Hypotenuse

The Unknown Below the Bar How Long Is the Kite String?A Leg Below the Bar Is the Answer Sensible?Recap: The Hypotenuse

7Elevation and Depression

Angle of Elevation Measuring From Eye Level Angle of Depression The Sun's Angle Two Triangles, One Height Recap: Looking Up and Down

2The Three Ratios

The Sine Ratio The Cosine Ratio Choosing the Ratio Recap: The Three Ratios

5Finding an Angle

Inverse Sine Inverse Cosine Inverse Tangent The Angle of a Ramp Both Acute Angles Recap: Finding an Angle

8Reciprocal Ratios

Cosecant, Secant, Cotangent Exact Reciprocal Values A Side From a Cosecant A Ladder and a Secant Recap: Reciprocal Ratios

3Finding a Side

Sides at Any Angle Rounding the Answer Tangent: Leg From Leg A Ladder Against a Wall The Other Acute Angle Recap: Finding a Side

6Special Triangles, Exactly

The Two Special Triangles An Exact Hypotenuse The Side Next to 30°An Exact Angle Recap: Exact Values

9Final Challenges

Is the Ladder Safe?The Wheelchair RampTwo Observers The Landing Plane The Kite The Sun's Angle, Exactly