In order to solve this problem, we must solve an equation.
First, we need to define our unknown.
Let's call our number "n".
So, the sum of the number and 6 is the same as saying n+6
Then we need to multiply it by 2 (since it's twice the sum)
2(n+6)
This whole thing is equal to three times of the difference of the number and 8
n-8 is equal to the difference between the number and 8, then we need to multiply it by three.
3(n-8)
now, we set both sides equal and solve
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The number is 36
You can use any letter but when you label it x you find x
Angle at centre = 2 x angle at circumference.
since angle BDC is 92 degrees, angle BAC will be 92/2 degrees