Answer:
63
Step-by-step explanation:
90+13x+1+28x+7=180
98+41x=180
41x=82
x=2
Plugging in the value of x, we get:
28x+7=28(2)+7=56+7=63
Answer:
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Step-by-step explanation:
Required
Show that:

To make the proof easier, I've added a screenshot of the triangle.
We make use of alternate angles to complete the proof.
In the attached triangle, the two angles beside
are alternate to
and 
i.e.


Using angle on a straight line theorem, we have:

Substitute values for (1) and (2)

Rewrite as:
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<em> -- proved</em>