A side of the triangle below has been extended to form an exterior angle of 76°. Find the value of x.

Top 51°

We know that the exterior angle of a triangle is equal to the sum of the two opposite interior angles. Let's call the angle adjacent to the extended side as angle A. Therefore, angle A + 51° = 76°.

Subtracting 51° from both sides gives us angle A = 25°.

Since angles in a triangle add up to 180°, the remaining angle opposite to the extended side is 180° - (76° + 25°) = 79°.

Now, we have a triangle with angles 25°, 51°, and 79°. Since the sum of the angles in a triangle is 180°, we can write:

25° + 51° + 79° = 180°

Simplifying the equation gives us:

155° = 180° - x

Rearranging the equation to solve for x gives us:

x = 180° - 155°

x = 25°

Therefore, the value of x is 25°.