Let’s solve the exercises one by one from the image. The problems involve finding the values of $x$ and $y$, using the principles of geometry, such as the properties of triangles and angles.

Exercise 25:

This triangle has:

• An angle labeled $x^\circ$,
• Another angle of $50^\circ$,
• The third angle labeled $y^\circ$.

Using the triangle angle sum property: $x + 50 + y = 180$ Solve for $x + y$: $x + y = 180 - 50 = 130$

Thus, $x + y = 130^\circ$. Further details might depend on the specific context of the problem.

Exercise 26:

This exercise involves an intersecting pair of triangles:

• $x^\circ$ and $y^\circ$ are opposite angles with one given as $125^\circ$.

By the property of vertically opposite angles: $x = 125^\circ$

The triangles also suggest isosceles properties where adjacent pairs of angles (labeled $y$) are congruent. Solve accordingly.

Exercise 27:

This triangle has:

• Two base angles of $25^\circ$,
• A vertex angle labeled $x^\circ$ and $y^\circ$.

Using the triangle angle sum property: $x + 25 + 25 = 180$ Solve for $x$: $x = 180 - 50 = 130^\circ$

Exercise 28:

This is an isosceles triangle:

• Two equal sides marked, one base labeled $7$,
• Angles labeled $x^\circ$ and $y^\circ$.

Use the triangle properties to find $x$ and $y$.

Would you like detailed step-by-step solutions or clarification for any of these problems? Let me know! Here are some related questions for practice:

1. How do the properties of isosceles triangles apply in these problems?
2. What is the sum of interior angles in any triangle?
3. How are vertically opposite angles used in geometric problems?
4. What methods can verify equal angles in an isosceles triangle?
5. How do supplementary angles relate to the exercises?

Tip: Always start by identifying given information and applying basic angle/triangle rules.