...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1.) may be demonstrated, either in common language, or by means of the signs used...

...of a triangle is less than the sum, but greater than the difference of the other two sides. 3. Tlie sum of the three angles of a triangle is equal to two right angles; and the external angle formed by producing one of its sides is equal to the sum of the t\vu...

...; but the sum of the two angles BAC, BAD, is equal to two right angles (theorem 1) ; therefore the sum of the three angles of a triangle is equal to two right angles. 80. COROLLARY 1. — If two angles of one triangle be equal to two angles of another triangle,...

...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1.) may be demonstrated, either in common language, or by means of the signs used...

...of the line, which have been proved to be together, equal to two right angles; therefore, also, the sum of the three angles of a triangle is equal to two right angles; as was to be demonstrated. Carol. When two angles of a triangle are given, the third angle...

...and the other equal to 105° 30', it will be easy to find the third angle, by recollecting that the sum of the three angles of a triangle is equal to two right angles (Geom. B. 1, Prop. 25,) or 180° ; therefore subtracting the sum of the two given, 47° + 105°...

...in any right-angled triangle, either n or w. be given, then n, с and w are all given; because the sum of the three angles of a triangle is equal to two right angles. Hence: с = 90°; n = 90° — w ; and w = 90° — n. Т E.) OBLIQUE-ANGLED PLANE TRIANGLES....

...in any right-angled triangle, a either n or w be given, then n, c and w are all given ; because the sum of the three angles of a triangle is equal to two right angles. Hence: c = 90°; n = 00° — w ; and w = <JO° — • n. No. tiiven. Sought. Equations. Logarithmic...

...is the sum of the two angles CBE, EBD, is equal to the sum of the two angles BAC, BCA. Cor. 1 . The sum of the three angles of a triangle is equal to two right angles ; for CBD-f-CBA is equal to two right angles (Prop. 1) ; now we have just seen that CBD is equal...

...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1,) may is' ' be demonstrated, either in common language, or by means of the signs...