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randRange(0,359) randRange(20,70)

Is the shown angle acute, right, or obtuse?

var ANGLE_TWO=ANGLE_ONE+DIFF,ANGLE_ONE_R=ANGLE_ONE*PI/180,ANGLE_TWO_R=ANGLE_TWO*PI/180;init({range:[[-11,31],[-10,10]],scale:20}),path([[5*cos(ANGLE_ONE_R),5*sin(ANGLE_ONE_R)],[0,0],[5*cos(ANGLE_TWO_R),5*sin(ANGLE_TWO_R)]]),DIFF==90?path([[1*cos(ANGLE_ONE_R),1*sin(ANGLE_ONE_R)],[sqrt(2)*cos(ANGLE_ONE_R+PI/4),sqrt(2)*sin(ANGLE_ONE_R+PI/4)],[1*cos(ANGLE_TWO_R),1*sin(ANGLE_TWO_R)]]):arc([0,0],1,ANGLE_ONE,ANGLE_TWO),addMouseLayer(),graph.protractor=new Protractor([22,0])

Acute

Acute
Right
Obtuse

graph.protractor.moveTo(0,0),graph.protractor.rotateTo(360-ANGLE_ONE),label([9*cos(toRadians(ANGLE_ONE+DIFF)),9*sin(toRadians(ANGLE_ONE+DIFF))],"\\color{"+PINK+"}{"+DIFF+"^{\\circ}}")

The shown angle measures less than 90^\circ.

label([9*cos(toRadians(ANGLE_ONE+DIFF)),9*sin(toRadians(ANGLE_ONE+DIFF))],"\\color{"+PINK+"}{"+DIFF+"^{\\circ}}")

Therefore, it is an acute angle.

90

Right

graph.protractor.moveTo(0,0),graph.protractor.rotateTo(360-ANGLE_ONE)

The shown angle measures 90^\circ.

label([9*cos(toRadians(ANGLE_ONE+DIFF)),9*sin(toRadians(ANGLE_ONE+DIFF))],"\\color{"+PINK+"}{"+DIFF+"^{\\circ}}")

Therefore, it is a right angle.

randRange(110,160)

Obtuse

graph.protractor.moveTo(0,0),graph.protractor.rotateTo(360-ANGLE_ONE)

The shown angle measures more than 90^\circ.

label([9*cos(toRadians(ANGLE_ONE+DIFF)),9*sin(toRadians(ANGLE_ONE+DIFF))],"\\color{"+PINK+"}{"+DIFF+"^{\\circ}}")

Therefore, it is an obtuse angle.

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