If the lines of the angle measure are short like the picture below then to get an accurate measurement, extend the angle's line until it passes the protractor. Normally, instead of moving the angle, you could actually move the protractor to the angle. This will make measuring easier. And then what you want to do is either rotate the angle or rotate the protractor. Do not make the mistake of beginning at the 180° mark. 2. The pdf file also has the answer sheet. Protractors are fun and easy to use. Tighten the wing nut to lock the angle in place. Now, add the acquired angle to 180°. Mathematics. Measure an Angle with a Protractor Measuring an Angle Protractor is a geometrical instrument that looks like the letter D. The angles are marked from 0° to 180° on the edge in clockwise direction as well as in anti-clockwise direction. 0. You must always line up one arm of the angle with the zero degree and then begin counting up from zero until they reach the next arm. A powerpoint to show how to use a 180 degree protractor to measure angles. The link to the image on Wikimedia is available below. Now, we use the following steps for required construction . It’s easier, however, to measure the angle when one side of it is on the zero line. Using a Protractor. I also have a copy of the protractor available in a Google Drawing. Use your protractor angle finder to measure the angle of the corner you are going to be working on. Using the zero line isn’t necessary because you can measure an angle by getting the difference in the degree measures of one line to the other. For example, if you counted 20° from the dotted line, the reflex angle measures 180 + 20 which is 200°. If an angle is less than 90 degrees, it's an acute angle. We use a protractor to measure angles.. Architects and designers use a more precise protractor called an angle protractor tool which gives more accurate measures. Find the cross or circle in the middle of your protractor. Protractor skills and the ability to measure angles will help guide your child through future topics such as Shapes and Trigonometry. How to use a 180° Protractor. gastonma. Line up one side of the angle with the zero line of the protractor (where you see the number 0). Measuring angles accurately In this video you will learn how to use a protractor to measure angles accurately. Save. How to measure an angle with a protractor: Place the midpoint of the protractor on the VERTEX of the angle. So I will type that in off the screen. How to measure an angle with a protractor: June 8, 2017 leesclassroom 1 Comment. Use the protractor to measure this angle. Edit. Follow the top line of the angle up to the measurements on the protractor's arc. 1.Taking X as centre and any radius daw an arc to Intersect the rays XA and XB, say at E and D, respectively. Have a look at this animation (press the play button) to see how to make a neat angle using a protractor and ruler: Trace along the inside of the T-bevel blade and handle. Line up one side of the angle with the zero line of the protractor (where you see the number 0). The worksheets are created dynamically, therefor you can create an unlimited number of measuring angles with a protractor worksheets. Read the number off the protractor where the second side of the angle meets the protractor. So we could say that the measure of angle BAC is equal to 30 degrees. Download Angle Meter™ and enjoy it on your iPhone, iPad, and iPod touch. This is a protractor, it helps you measure angles (in degrees):. To measure an acute angle without a protractor, start by drawing a vertical line connecting the 2 rays of the angle to form a right triangle.