Question

AngleDCE=60°, prove that AB||DC.​

Answer 1

4x +3x + 2x = 180

9x=180

x=180/9

=20

4,* 20=80

3*20 =60

2*20 =40

so 3x =60

so parallel

Answer 2

Step-by-step explanation:

in triangle ABC

in triangle ABC2x+3x+4x=180degree

in triangle ABC2x+3x+4x=180degree9x=180 degree

x= 20 degrees

angle A =2multiply 20 =40 degrees

since 4x =4multiply 20 =80 degree

80 +60+angleC =180

angle C =40

angle A=Angle C

they form alt. int. angle

= AB // CD