How to Calculate Angles for a Handyman
- 1). Stand facing the angle.
- 2). Pick an arbitrary point along the object to the left. For convenience, choose a point within a foot or so of the angle, if possible.
- 3). Place one end of the measuring tape against the point so it is perpendicular to the object and makes a right angle with the left object.
- 4). Measure across perpendicularly until you hit the object on the right. Note the length between the two objects. Label this length "B."
- 5). Measure the distance between the point chosen earlier and the point of intersection between the two objects. Label this length "A."
- 6). Measure the distance between the point of intersection and the point on the right object where the measuring tape touched. Label this length "C."
- 7). Divide length "A" by length "C." This results in the cosine of the angle.
- 8). Press the arccosine button on the scientific calculator. This button is most commonly labeled "Cos^-1," "Acos" or "ArcCos."
- 9). Input the cosine value calculated previously.
- 10
Press the "Enter" or "Answer" button. The value returned is the angle required to generate that particular cosine value measure previously and is the angle generated by the two intersecting objects.
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