2007-02-12 02:30:46 · 10 answers · asked by Tie 1 in Science & Mathematics ➔ Mathematics
the sum of 3 angles in triangle is always 180 degree
A+B+C=180
(A = first angle, B=second angle, C= third angle)
we want to find C
put the values for first second angles
21+86+C=180
107+C=180
subtract both sides by 107
C=180-107= 73 degree
good luck
2007-02-12 02:36:03 · answer #1 · answered by Helper 6 · 0⤊ 0⤋
The angles of all triangles add up to 180. So the missing angle is 180 - 21 - 86.
The result is left as an exercise to the reader. :)
2007-02-12 02:34:24 · answer #2 · answered by Meg W 5 · 1⤊ 0⤋
the sum of the angles is 180°
so the third angle has 180- (21+86) = 73°
2007-02-12 02:34:23 · answer #3 · answered by maussy 7 · 0⤊ 0⤋
Let third angle be x°
21 + 86 + x = 180
107 + x = 180
x = 76
Measure of third angle = 76°
2007-02-12 02:59:33 · answer #4 · answered by Como 7 · 0⤊ 0⤋
21+86=107 so the third is 180-107 or 73
73 degrees
2007-02-12 02:34:10 · answer #5 · answered by Dan 1 · 1⤊ 0⤋
180-(21+86)
180-107
= 73
2007-02-12 05:18:21 · answer #6 · answered by Anonymous · 0⤊ 0⤋
73 degrees
Any of these questions always want your angles to add up to 180 degrees. 180 degrees is the angle of a straight line. When you are given two angles, the 3rd angle is just 180 degrees minus the sum of the other two angles.
2007-02-12 02:34:19 · answer #7 · answered by daveypa22 4 · 0⤊ 0⤋
21+86+x=180d
so x=73degrees
2007-02-12 02:44:36 · answer #8 · answered by ahl_090 2 · 0⤊ 0⤋
They have to add up to 180.
180- (21+86)=73
2007-02-12 02:34:34 · answer #9 · answered by jjayferg 5 · 0⤊ 0⤋
let
x = Third angle
- - - - - - - -
x + 21 + 86 = 180
x + 107 = 180
x + 107 - 107 = 180 - 107
x = 73
The third angle is 73 degrees
- - - - - - - - -s-
2007-02-12 06:21:12 · answer #10 · answered by SAMUEL D 7 · 0⤊ 0⤋