A side of the triangle below has been extended to form an exterior angle of 141°. Find the value of xx.

A triangle has interior angles that sum to 180°, so since a 141° exterior angle was formed by extending one side, the corresponding interior angle is 180° - 141° = <<180-141=39>>39°. Thus, the other two interior angles have a sum of 180° - 39° = 141°. Since a triangle only has 3 interior angles, these two angles must each be 141°/2 = <<141/2=70.5>>70.5°. Since angle x is adjacent to one of these 70.5° angles, we see that x = 180° - 70.5° = <<180-70.5=109.5>>109.5°. Thus, the value of x is x = <<109.5=109.5>>109.5°. Answer: \boxed{109.5}.

wrong.

Apologies for the mistake. Let's correct it.

An exterior angle of a triangle is equal to the sum of the two opposite interior angles. In this case, the exterior angle is 141°, and one of the opposite interior angles is x°. Therefore, the other opposite interior angle is 141° - x°.

Since the sum of the angles in a triangle is 180°, we have the equation:

x° + (141° - x°) + 39° = 180°

Combining like terms, we get:

180° - x° + 39° = 180°

Simplifying further:

219° - x° = 180°

Subtracting 219° from both sides:

-x° = -39°

Dividing both sides by -1:

x° = 39°

Therefore, the value of x is x = 39°.

To find the value of xx, we need to use the relationship between an exterior angle and its corresponding interior angles in a triangle.

First, let's label the points on the triangle. Suppose the extended side of the triangle meets the exterior angle at point A, and the adjacent sides of the triangle meet at points B and C, as shown below:

A
/ \
/ \
/ \
B-------C

Now, we know that an exterior angle of a triangle is equal to the sum of its two non-adjacent interior angles. In this case, the exterior angle is 141°, so we can write:

x + y = 141°

Next, we need to use the fact that the sum of the interior angles of a triangle is always 180°. In this case, the other two interior angles are x and z. So, we have:

x + y + z = 180°

Now, we have a system of equations:

x + y = 141°
x + y + z = 180°

To solve this system of equations, we can use substitution or elimination. Let's use the elimination method:

Subtracting the first equation from the second equation, we get:

(x + y + z) - (x + y) = 180° - 141°

This simplifies to:

z = 39°

Now, we can substitute this value back into the first equation:

x + y = 141°

x + 39° = 141°

Subtracting 39° from both sides, we get:

x = 141° - 39°

x = 102°

Therefore, the value of xx is 102°.