ABC is a triangle. What is the size of the angle ?
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ABC is a triangle. What is the size of the angle ?
First, let's find the value of angle B.
Since the sum of angles in a triangle is equal to 180, the formula is:
Now let's look at angle ADB, we can calculate its value since we are given angle ADC.
Now we can calculate angle BAD:
56
Indicates which angle is greater
Because angle ADC is outside triangle BAD! You need the interior angle ADB, which is since angles on a straight line sum to 180°.
Look for the triangle that contains the angle you're asked to find. Since we want angle BAD, we need triangle BAD, not triangle ABC.
Angle ABC is in the original triangle, while angle ABD is part of triangle BAD. They're the same angle in this problem since both refer to angle B in triangle ABC.
This finds angle B in triangle ABC. We need this angle because it's also angle ABD in triangle BAD, which helps us solve for angle BAD.
Add all three angles in triangle BAD: . If they sum to exactly 180°, your answer is correct!
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