What if there’s no protractor in hand? Worry no even more bereason you can meacertain an angle even with no protractor.

You are watching: How to measure angles without a protractor

Here’s how:

Tip 1: Get a ruler and also meacertain the specific distance of both sides from the beginning point of the angle (Should be the identical distance for both sides). Take a pen and paper to document all the measurements.

Tip 2: Label the distance as “D” and also mark the 2 points on the angle. It must be a size away from the point of origin. Labeling after you measure it will certainly assist you identify each angle point quickly.

Step 3: Use the leader again to uncover the specific distance between the two points on the angle and also record the measurements on the paper.

Step 4: You will should label the measured distance between the two points as “E.” This is to differentiate it from the previous measurement you did. Failure to record will certainly result in confusion while doing measurements and also calculations in the future.

Tip 5: Apply this Sine Formula: Angle meacertain = 2 x arcsin (0.5 x e/d). Input the values you’ve measured formerly for “D” and “E.”

Step 6: In addition, this formula is acquired from the actual equation for the offered sine actions of the side of the appropriate triangle. The angle’s sine need to be equal to the measurement of the opposite side of the angle and split by the measurement of the triangle’s hypotenusage.

Tip 7: Solve the angle meacertain making use of your graphing calculator. Encode number “2” and press the multiplication symbol. Then push “arcsin” and also the worth that is half of “D” and “E.”

Tip 8: Double-check the encoded worths, then push “Enter” or the “=” sign to get the last answer or solution. Make sure you’ve encoded the ideal worths appropriately, or you will certainly obtain the wrong answer.

Step 9: For this formula, you deserve to likewise use the calculator’s second vital to settle it. Just push “arcsin,” which you deserve to watch from the very same key as the sin.

Step 10: You must get the final answer effectively as quickly as you reach this step. If you have actually a protractor or plans to grab one, later, you can verify your answer and also check if they were exact or not.

You deserve to additionally bisect angles without a protactor

There’s a lot that you deserve to do various other than measuring without a protractor. Talking back going earlier to basics, you have the right to likewise bisect angles without using a protractor. For a quick refresher, bisecting an angle implies to divide the angle into two equal components. That’s the line that you view that splits an angle into two equal parts.

Here’s exactly how to bisect the angles without a protractor:

Step 1: Use a compass to and place it on the vertex of the angle, which is allude B.

Tip 2: You will certainly have to attract an arc from across each arm of the angle.

Tip 3: Position your compass on the suggest wright here it intersects an arm and attract an additional arc on the inside of the angle.

Tip 4: Repeat the same procedure for the various other arm without transforming the compass’ width so that the two arms will intersect from each other.Tip 5: By utilizing a ruler, affix the vertex to the suggest wbelow the arcs intersect, which is at allude D. The bisector of ABC is DB.

Tip 6: To bisect the angles, usage your compass and also ruler for accuracy.

Constructing Special Angles without a Protractor

Tip 1: You will have to attract a line segment of points L and also M.

Step 2: Draw an arc across LM that goes up over allude L.

Step 3: Move the compass to the direction wright here the suggest of the arc intersects point LM. Make certain you did not change the width of the compass.

Step 4: Draw another arc that crosses the first arc that you attracted.

Tip 5: Then affix allude L to the suggest where the 2 arcs satisfy.

Important things to remember

Ensure that you make measurements accurately. It’s constantly recommfinished to conduct measurements at leastern twice to verify its correctness.It won’t hurt to compare your answers once making use of a protractor. This will certainly aid you exercise and also learn better.

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There you have it! It could be much easier to measure, bisect, and construct angles using protractors. However before, it’s additionally great to note that you can actually do it without it. Your geomeattempt skills will certainly additionally boost when you start doing it manually. So the following time you don’t have a protractor, you’re good to go!

Can you use a ruler instead of a protractor?


A protractor is the usual tool for the project. When a protractor is not easily accessible, but, an simple ruler and a calculator will suffice. Hold one of the lines so that it is level with the ground.