a) Take three collinear points P, Q, R in a plane. Join PQ, QR, and RP. Is the figure a triangle? If not, why?
b) Can a triangle have two obtuse angles?
c) One of the acute angles of a right triangle is 40.5°. Find the other acute angle.
The answer with the best explanation will be marked as the brainliest
1) collinear means 3 points lies in a single line
thats way it is not forms a triangle.
2) No because obtuse angles means more then 90 soo if we take 2 obtuse anges is more then 180 degree… according to law of tri angles sum of three angles = 180.
so in a tri angle only one obtuse angle should be taken.
3)in triangle three angles sum = 180
so one the angle = 90 and other = 40.5
so 90+40.5+x = 180
then x = 180- 130.5
x = 49.5
Answer:
a) No. The figure formed is a line and not a triangle. Because all points are collinear i.e. all the points are in the same line.
b)No. A triangle cannot include two obtuse angles. Because the sum of the measure of all angles of a triangle is 180° and if there is one obtuse angle for e.g. 120° then the other one needs to be acute angle i.e. for this eg- it needs to be smaller than 90°.
c)If one angle is 90° and the other is 40.5° then,
90 + 40.5 + x = 180 ——– Sum of measure of angles of a triangle
130.5 + x = 180
x = 180 – 130.5
:. x = 49.5°