Alpha, Beta and Gamma are inner angles in a triangle. If Alpha = Beta + Gamma, what can't be the size of Beta?  Choose the correct choice from the following choices:
A) 44 degrees	B) 45 degrees.	C) 89 degrees	D) 90 degrees.	E) There isn't enough data to determine.
Given Alpha = Beta + Gamma, and Alpha, Beta and Gamma are inner angles in a triangle. Thus Alpha + Beta + Gamma = 180   Beta + Gamma + Beta + Gamma = 180 =&gt; 2(Beta + Gamma) = 180 =&gt; Beta + Gamma = 90. Thus beta will be less than 90.   Hence the answer is 90 degrees..
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Alpha, Beta and Gamma are inner angles in a triangle. If Alpha = Beta + Gamma, what can't be the size of Beta?