13. Flowcharts Classify Triangles by Angles

The pseudocode below checks to see if a triangle has all angles less than 90 degrees, one angle equal to 90 degrees, or one angle greater than 90 degrees, and classifies it accordingly.

ALGORITHM triangleAngleType()

BEGIN
    INPUT angleA, angleB, angleC

    IF angleA + angleB + angleC ≠ 180 THEN
        PRINT "Not a valid triangle."
    ELSEIF angleA < 90 AND angleB < 90 AND angleC < 90 THEN
        PRINT "Acute triangle."
    ELSEIF angleA = 90 OR angleB = 90 OR angleC = 90 THEN
        PRINT "Right triangle."
    ELSEIF angleA > 90 OR angleB > 90 OR angleC > 90 THEN
        PRINT "Obtuse triangle."
    ENDIF
END

Tasks

1. In the pseudocode, why has ELSEIF angleA > 90 OR angleB > 90 OR angleC > 90 THEN been replaced with just ELSE?

2. In the flowchart, fill in the missing text.

   

Q1

In the pseudocode, why has ELSEIF angleA > 90 OR angleB > 90 OR angleC > 90 THEN been replaced with just ELSE?

All other possibilities have been tested for,
so an obtuse triangle is the last possibility,
so it doesn't need testing to confirm it.

Q2

In the flowchart, fill in the missing text.