I WILL AWARD BRAINLIEST!!!
Find the value of x in each case
B, C ∈ AD
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So first let's find ∠BCE: (Assume that the line ABCD is a straight line)
The angle on a line is 180°.
So ∠BCE = 180° - 64° - 90° = 26°
Now, let's find ∠EBC:
∠EBC = 180° - 3x.
The sum of the angles in a triangle is also 180°. So if you add up the angles in the triangle, you should get 180°.
∠BCE + ∠EBC + ∠BEC = 180°
26° + (180° - 3x) + x = 180°
Now, combine like terms:
206° - 2x = 180°
Subtract both sides by 206°.
-2x = -26
Divide both sides by -2 and you'll get:
x = 13°.