The answer is: " -5/3 " ; or, write as: " -1 ⅔ " .
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Explanation:
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(-5/6) + (-5/6) = (-5/6) <span>− (5/6) ;
------> {since: "adding a negative" is the same a "subtracting a positive"} ;
------> </span> (-5/6) − (5/6) = (-5 − 5) / 6 ;
= -10/6 = (-10/2) / (6/2) ;
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= " -5/3 " ; or, write as: " -1 ⅔ " .
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J -60
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First find the equation of y.
Find the slope m.
.
Pick one point, I'll pick (-3, 9). Insert coordinates in equation then compute n.
.
The equation of a line y is:
.
The perpendicular line 
is same like the normal line except its slope m becomes:
.
The equation of a perpendicular bisector is thus:
.
Hope this helps.
Measure 1 would be 59 degrees (180-121)
Measure 2 would be 121 degrees (vertical angle theorem)
