Step 1 :Step 1: Understand that a 12% grade means that for every 100 units of distance travelled horizontally, you ascend 12 units vertically. This forms a right triangle where the hypotenuse is the road, the horizontal leg is 100 units, and the vertical leg is 12 units.
Step 2 :Step 2: Use the tangent function to find the angle. The tangent of an angle in a right triangle is the length of the opposite side divided by the length of the adjacent side. So, \( \tan(\theta) = \frac{12}{100} = 0.12 \)
Step 3 :Step 3: Use the inverse tangent function (also called the arctangent) to find the angle in radians. \( \theta = \arctan(0.12) \)
Step 4 :Step 4: Convert the angle from radians to degrees by multiplying by \( \frac{180}{\pi} \). So, \( \theta = \arctan(0.12) \times \frac{180}{\pi} \)