Q:

What will be angle COD If: angle COD minus angle KOD equals 61degrees and angle COD minus angle KOC equals 53degrees?

Accepted Solution

A:

Use algebra for such problems
let, Angle COD = x
Angle KOD = y
Angle KPC = z
Given ,. x - y = 61° ( Equation 1 )
x - z = 53° ( Equation 2 )
Subtract 1st equation from 2nd and you'll get :

z - y = 8° ( Equation 3 )
Now since , x + y + z = 180° ( Equation 4 )
Add Equation 3 to Equation 4 and you'll get
x + 2z = 188° ( Equation 5)
From Equation 2 we know that , x -z = 53°
or, x = 53° + z ( Equation 6 )
Put this value of 'x' in Equation 5 and solve for z. you'll get :
(53° + z) + 2z = 188°
or
3z = 188 - 53 = 135°
solving for z we get
z = 45°
put this value of z in Equation 5
x + ( 2 x 45° ) = 188°
or
x = 188° - 90° = 98°
hence , Angle COD = 98°