Does anyone know how to do this I quite don’t understand?
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Answer:
Step-by-step explanation:
This triangle is isosceles. That means that two angles are equal and thus two sides are equal: Since FG = 18 in, EF is also 18 in.
The sum of the interior angles must be 180 degrees. Therefore,
23 deg + 23 deg + <F = 180 deg, or
<F = (180 - 46) deg = 134 deg.