12. Find the measure of each interior angle of triangle QRT.
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Answer:
[tex]\angle QRT=125.6\°[/tex]
[tex]\angle RTQ=6.4\°[/tex]
[tex]\angle TQR=48\°[/tex]
Step-by-step explanation:
It is important to remember that, by definition, the measure of an exterior angle of a triangle is equal to the sum of the measures of the two non-adjacent interior angles.
In this case we can idenfity that the angle [tex]17x[/tex] is an exterior angle of the triangle QRT. Then:
[tex]17x=\angle RTQ+\angle TQR[/tex]
Where:
[tex]\angle RTQ=2x\\\\\angle TQR=48\°[/tex]
Substituting values and solving for "x", we get:
[tex]17x=2x+48\\\\17x-2x=48\\\\15x=48\\\\x=3.2[/tex]
Then:
[tex]17x=17(3.2)=54.4\°\\\\\\\angle RTQ=2(3.2)=6.4\°[/tex]
The sum of the interior angles of a triangle is 180°, therefore:
[tex]\angle QRT+\angle RTQ+\angle TQR=180[/tex]
Solving for [tex]\angle QRT[/tex], we get:
[tex]\angle QRT=180-48-6.4=125.6\°[/tex]