21. In the figure given below, AC is parallel to DE. Find the valuesof xy and z and hence find the 2DBE.
21-70X
509
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Answer:
X= 50°
Y= 70°
Z= 30°
BDE= 30°
2BDE= 60°
Step-by-step explanation:
(2x -70 )+z+(2x+20)=180...(sum of angle on a straight line)
2x -70 = BDE... alternate angles
Y + (2x-70)+(50+x-20) = 180...(sum of angles in a triangle)
X-20 = z ... alternate and opposite angles
(2x -70 )+z+(2x-+20)=180
2x-70 + x-20 +2x +20= 180
5x -70= 180
5x = 250
X= 50°
X-20 = z
50-20= z
30° = z
2x -70 = BDE
2(50) -70 = BDE
100-70 = BDE
30°= BDE
Y + (2x-70)+(50+x-20)
Y + 100-70 +50 +50 -20 = 180
Y + 200-90=180
Y= 70°
2BDE = 2*30
2BDE= 60°