Find the value of x in each triangle. Give your reasons.

The markings on two sides indicate that it is an isosceles triangle.

The angle $65^\circ$ is opposite one of the equal sides, and $x^\circ$ is opposite the other equal side.

Reason: Base angles of an isosceles triangle are equal.
The value of $x$ is $\boxed{\text{65}}$.

The markings on two sides indicate that it is an isosceles triangle.

The angle $70^\circ$ is one of the base angles, and $x^\circ$ is the other base angle.

Reason: Base angles of an isosceles triangle are equal.
The value of $x$ is $\boxed{\text{70}}$.

The markings on two sides indicate that it is an isosceles triangle.

Let the base angles be $y^\circ$. The vertex angle is $62^\circ$.

Reason: Base angles of an isosceles triangle are equal, and the sum of angles in a triangle is $180^\circ$.
The value of $x$ is $\boxed{\text{59}}$.

The markings on two sides indicate that it is an isosceles triangle.

Let the base angles be $y^\circ$. The vertex angle is $36^\circ$.

Reason: Base angles of an isosceles triangle are equal, and the sum of angles in a triangle is $180^\circ$.
The value of $x$ is $\boxed{\text{72}}$.

The markings on two sides indicate that it is an isosceles triangle.

Let the base angles be $y^\circ$. The vertex angle is $40^\circ$.

Reason: Base angles of an isosceles triangle are equal, and the sum of angles in a triangle is $180^\circ$.
The value of $x$ is $\boxed{\text{70}}$.

The markings on two sides indicate that it is an isosceles triangle.

The interior angle adjacent to it forms a linear pair.

Since the base angles are equal, the other base angle is also $50^\circ$.

The angle $x^\circ$ is the vertex angle.

Reason: Angles on a straight line sum to $180^\circ$, base angles of an isosceles triangle are equal, and the sum of angles in a triangle is $180^\circ$.
The value of $x$ is $\boxed{\text{80}}$.