I believe it is the linear pair theorem because the theorem is if two angles form a linear pair, then they are supplementary.
Answer:
2x^2+10x+8
Step-by-step explanation:
(2x+2)(x+4)
=(2x+2)(x+4)
=(2x)(x)+(2x)(4)+(2)(x)+(2)(4)
=2x^2+8x+2x+8
=2x^2+10x+8
<h3>
Answer: 1.3</h3>
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Work Shown:
The two points we have are
and 
Apply the distance formula

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A shortcut is possible by subtracting the y coordinates of the two points, and making the result positive through the use of absolute value.
So we either say
|y1-y2| = |1.2-2.5| = |-1.3| = 1.3
or,
|y2 - y1| = |2.5 - 1.2| = |1.3| = 1.3
We get the same result. This shortcut is valid because the x coordinates of both points are the same.
The interior angles of any triangle sum to 180°, so
(12<em>x</em> + 2) + 26<em>x</em> + (6<em>x</em> + 2) = 180
44<em>x</em> + 4 = 180
44<em>x</em> = 176
<em>x</em> = 176/44 = 4