Question

Write 'T' for true and 'F' for false

(i) If two parallel lines are cut by a transversal, then the alternate interior angles are equal.
(ii) If two lines intersect each other, then the vertically opposite angles are equal.
(iii) Each acute angle of an isosceles right triangle measures 60°.
(iv) A right triangle cannot have an obtuse angle.

Answer 1

$$\begin{gathered} \begin{array}{l}\\ \left(\text{i}\right)\text{True}\\ \left(\text{ii}\right)\text{True}\\ \left(\text{iii}\right){\text{False. Each acute angle of an isoceles right triangle measures 45°.}}^{}\\ \left(\text{iv}\right)\text{True. This is because the sum of three angles of a triangle must be 180°.}\end{array} \\ \mathrm{So,\; if\; one\; of}{\text{the angles is 90°, the sum of the other two angles must also be 90°}}^{}\text{.} \\ \mathrm{So},\text{none of the angles can be greater than 90°.} \end{gathered}$$