In the given figure, $AB\parallel CD$. Find the value of $x$.

In the given figure, $l\parallel m$. Find the value of $b-a$.

Which of the following is/are point symmetric?

Which of the following has an infinite number of lines of symmetry?

The sum of an angle and half its complementary angle is $75°$. Find the angle.

The adjacent angles of a rhombus are $2x-35° \mathrm{and} x+5°$. Find $x$.

In the figure above, $ABCD$ is a parallelogram, and if $AC=14 \mathrm{cm} \mathrm{and} BD=10 \mathrm{cm}$, $AP+BP=$ _____ $\mathrm{cm}$.

The following steps are involved in finding the largest angle of a quadrilateral $PQRS$, if $\angle P:\angle Q:\angle R:\angle S=1:2:3:4$. Arrange them in sequential order.
(A) $10x=360°\Rightarrow x=36°$

(B) Let the angles be $\angle P=x, \angle Q=2x, \angle R=3x \mathrm{and} \angle S=4x$.

(C) The largest angle $=4\left(36°\right)=144°$

(D) Given $\angle P:\angle Q:\angle R:\angle S=1:2:3:4$

(E) $\angle P+\angle Q+\angle R+\angle S=360°\Rightarrow x+2x+3x+4x=360°$

The following steps are involved in finding the third side of an isosceles triangle whose two sides are $6 \mathrm{cm} \mathrm{and} 12 \mathrm{cm}$. Arrange them in sequential order. 
(A) But the difference between two sides is less than the third side.
(B) Since the given triangle is isosceles, the possible measure of the third side is either $6 \mathrm{cm} \mathrm{or} 12 \mathrm{cm}$.
(C) The measure of the third side is $12 \mathrm{cm}$.
(D) $6 \mathrm{cm}$ cannot be the measure of the third side.