 | George Albert Wentworth, David Eugene Smith - Arithmetic - 1912 - 374 pages
...and OB is perpendicular to OA. A right angle, therefore, contains J of 360 degrees, or 90 degrees. An angle less than a right angle is called an acute angle, and one greater than a right angle is called an obtuse angle. 136. Angle Measure and Arc Measure. The... | |
 | George Albert Wentworth, David Eugene Smith - Geometry - 1913 - 496 pages
...angle. In like manner, it follows that a straight angle equals twice a right angle. 35. Acute Angle. An angle less than a right angle is called an acute angle. For example, the angle m, as shown in this figure, is an acute angle. 36. Obtuse Angle. An angle greater... | |
 | Earle Bertram Norris, Kenneth Gardner Smith, Ralph Thurman Craigo - Arithmetic - 1913 - 234 pages
...perpendicular to each other. In Fig. 47 each of the angles BOG, CO A, AOD, and BOD is a right angle. An angle less than a right angle is called an acute angle. Thus Z-BOD in Fig. 48 is an acute angle. An angle greater than a right angle is called an obtuse angle.... | |
 | George Howe - Mathematics - 1915 - 168 pages
...angle Fig. 7. MATHEMATICS between the lines А В and CD, which are perpendicular to each other. XIII. An angle less than a right angle is called an acute angle. XIV. An angle greater than a right angle is called an obtuse angle. XV. The addition of two right angles... | |
 | Nelson L. Roray - Arithmetic - 1916 - 172 pages
...Name other straight angles. How many degrees in a straight angle? How many right angles? FIG. 5. 10. An angle less than a right angle is called an acute angle. 11. An angle greater than a right angle but less than a straight angle is called an obtuse angle. ANGLES... | |
 | Earle Raymond Hedrick - Geometrical drawing - 1916 - 89 pages
...and an angle of 25° at another. Measure the third angle. Is the sum of all three angles 180°? 13. An angle less than a right angle is called an acute angle. A triangle with one right angle is called a right triangle. Draw a right triangle, and measure the... | |
 | Mabel Sykes, Clarence Elmer Comstock - Geometry, Modern - 1918 - 344 pages
...*' AOAs is called a straight angle. The angle formed by one complete rotation is called a perigon. An angle less than a right angle is called an acute...An angle greater than a right angle and less than a straight angle is called an obtuse angle. 19. To construct a perpendicular to a line from a given... | |
 | Herbert Ellsworth Slaught, Nels Johann Lennes - Geometry, Plane - 1918 - 360 pages
...Acute, Obtuse, and Reflex Angles. An acute angle is an angle less than a right angle. An obtuse angle is an angle greater than a right angle and less than two right angles. A reflex angle is an angle greater than two right angles, and less than four right angles. Acute and... | |
 | Herbert Ellsworth Slaught - 1918 - 344 pages
...Acute, Obtuse, and Reflex Angles. An acute angle is an angle less than a right angle. An obtuse angle is an angle greater than a right angle and less than two right angles. A reflex angle is an angle greater than two right angles, and less than four right angles. Acute and... | |
 | Raleigh Schorling, William David Reeve - Mathematics - 1919 - 510 pages
...T FIG. 81. ACUTE ANGLE FIG. 32. OBTUSE ANGLE the right angle, the straight angle, and the perigon. An angle less than a right angle is called an acute angle, Fig. 31. An angle which is greater than a right angle and is less than a straight angle is called an... | |
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An angle less than a right angle is called an acute angle; an angle greater than a right angle and less than two right angles is called an obtuse angle. 
