Question

Name the types of following triangles:
(i) Triangle with lengths of sides 7 cm, 8 cm and 9 cm.
(ii) ΔPQR such that PQ = QR = PR = 5 cm.
(iii) ΔDEF with m ∠D = ${90}^{\circ }$
(iv) ΔXYZ with ∠Y = ${90}^{\circ }$ and XY = YZ.

Answer 1

(i) Lengths of sides of a triangle are 7 cm, 8 cm and 9 cm respectively. Therefore, it is an scalene triangle.
(ii) In $△PQR$,
PQ = QR = PR = 5 cm
Since all sides are equal to each other. Therefore, $△PQR$ is an equilateral triangle.
(iii) In $△DEF,m\angle D={90}^{\circ }$
Thus, $△DEF$ is a right angled triangle.
(iv) In, $△XYZ$
Length of two sides are equal (XY=YZ) and $\angle Y={90}^{\circ }$
Therefore, $△XYZ$ is a right angles isosceles triangle.