The angle subtended by an arc at the center is double the angle subtended by it at any point on the circumference.
In the second diagram, we have a circle with center B. This implies that B is the center of the circle. However, the diagram labels points A, B, C, D on the circumference. Let's assume the center is O (as in the first diagram), or interpret the labeling differently.
Looking at the second diagram, it appears to be a circle with points A, B, C, D on the circumference. There is no explicit center labeled.
Let's assume the question is related to inscribed angles and arc measures.
We are given that arc CD subtends an angle of 68 degrees at point A (angle CAD). This means the measure of arc CD is 2 * 68 = 136 degrees. However, the diagram shows 68 degrees near point D, and labeled as angle ACD. If angle ACD = 68 degrees, then the arc AD = 2 * 68 = 136 degrees.
Let's interpret the number 68° next to D as an angle related to chord CD. It is likely the inscribed angle subtended by arc AD at point C. So, angle ACD = 68 degrees. This implies arc AD = 2 * 68 = 136 degrees.
We are given that angle ABC = y. This angle subtends arc AC.
We are given that angle ADC = 146 degrees. This is an inscribed angle. This cannot be correct as inscribed angles subtended by a diameter are 90 degrees, and angles subtended by a major arc are less than 180 degrees, and angles subtended by a minor arc are less than 180 degrees. An inscribed angle cannot be 146 degrees if it subtends a minor arc. If it subtends a major arc, the remaining arc would be very small.
Let's assume 146° is the measure of arc BC.
If arc BC = 146 degrees, then the inscribed angle BAC = 146 / 2 = 73 degrees.
Let's assume 68° is the measure of arc AB.
If arc AB = 68 degrees, then the inscribed angle ACB = 68 / 2 = 34 degrees.
Let's assume the diagram means: Angle CAD = 68 degrees, and Angle ABD = y. And some other information is missing.
Let's re-examine the image. In the second diagram, we have points A, B, C, D on the circle. We have angles labeled: y, 146°, 68°, x.
It seems the numbers 146 and 68 are arc measures, not inscribed angles.
Let arc BC = 146 degrees.
Let arc AB = 68 degrees.
The angle y is inscribed angle ADC. The arc subtended by y is arc AC. Arc AC = Arc AB + Arc BC = 68 + 146 = 214 degrees. So, y = 214 / 2 = 107 degrees. This is unlikely as y looks acute.
Let's assume 146° is the measure of arc ADC, or something similar.
Let's reconsider the first diagram for clues on how angles and arcs are labeled. In the first diagram, 130° is clearly labeled as an arc measure (arc AB). 63° is an inscribed angle (angle ABC). 'x' is a central angle (angle AOC).
Applying this to the second diagram:
Let arc AB = y.
Let arc BC = 146°.
Let arc CD = 68°.
Let arc DA = x.
The sum of arcs in a circle is 360°. So, y + 146° + 68° + x = 360°.
y + x + 214° = 360°.
y + x = 360° - 214° = 146°.
We need to find y and x. We don't have enough information.
Let's assume 'y' is an inscribed angle subtending arc AC. Arc AC = arc AB + arc BC = y + 146°. So inscribed angle ADC = (y + 146°)/2.
Let's assume 'x' is an inscribed angle subtending arc BC. Arc BC = 146°. So inscribed angle BAC = 146°/2 = 73°.
Let's assume the labeling refers to arcs:
Arc BC = 146°.
Arc CD = 68°.
Angle labeled 'y' is an inscribed angle subtending arc AC.
Angle labeled 'x' is an inscribed angle subtending arc AD.
We know that arc AB + arc BC + arc CD + arc DA = 360°.
arc AB + 146° + 68° + arc DA = 360°.
arc AB + arc DA = 360° - 146° - 68° = 146°.
Let's reinterpret the labels as inscribed angles.
If y = angle ABC, then arc AC = 2y.
If 146° = angle ADC, this is too large for an inscribed angle unless it's a reflex angle or related to the opposite arc.
Let's assume the numbers are arc measures.
Arc BC = 146°.
Arc CD = 68°.
We need to find x and y.
Consider the inscribed angle subtended by arc CD at point B. This is angle CBD. Arc CD = 68°. So, angle CBD = 68°/2 = 34°.
Consider the inscribed angle subtended by arc BC at point D. This is angle BDC. Arc BC = 146°. So, angle BDC = 146°/2 = 73°.
Now consider triangle BCD. The sum of angles is 180°. Angle BCD + angle CBD + angle BDC = 180°.
We need angle BCD.
Let's look at the variable 'y'. It is placed near point B, as if it's angle ABC. If angle ABC = y, it subtends arc AC. Arc AC = arc AB + arc BC.
Let's assume 'x' is angle ABD. It subtends arc AD.
This problem is ambiguous without a clear indication of what the numbers and letters represent (arcs or angles, and which angles).
Let's assume the standard convention where numbers next to arcs are arc measures and letters with degree symbols are angles.
Let's assume the diagram intends for 'y' to be the inscribed angle subtending arc AC, and 'x' to be the inscribed angle subtending arc AD.
The numbers 146° and 68° are also labeled. Given their positions, they are likely arc measures.
Let arc BC = 146°.
Let arc CD = 68°.
We know that arc AB + arc BC + arc CD + arc DA = 360°.
arc AB + 146° + 68° + arc DA = 360°.
arc AB + arc DA = 360° - 146° - 68° = 146°.
Now let's look at the labels 'y' and 'x'.
'y' is placed such that it seems to represent the inscribed angle subtending arc AC. Arc AC = arc AB + arc BC. So, y = (arc AB + 146°)/2.
'x' is placed such that it seems to represent the inscribed angle subtending arc AD. So, x = arc AD / 2.
We have two unknowns (arc AB, arc AD) and one equation (arc AB + arc AD = 146°). We need more information.
Let's consider another interpretation: maybe y and x are arc measures.
Let arc AB = y.
Let arc AD = x.
We already established y + x = 146°.
Let's assume the angles are labeled.
Angle ABC = y. This subtends arc AC. Arc AC = arc AB + arc BC.
Angle ADC = 146 degrees. This is too large.
Let's go back to arc measures.
Arc BC = 146°. Arc CD = 68°. Arc AB + Arc AD = 146°.
What if y is the inscribed angle subtending arc AC, and x is the inscribed angle subtending arc BC?
If x = inscribed angle BAC, then x = arc BC / 2 = 146° / 2 = 73°. This doesn't match the label.
If y = inscribed angle ABC, then arc AC = 2y.
Let's assume the labels x and y are inscribed angles.
Angle ADC = 146°. This is very likely an arc measure of the major arc AC. The minor arc AC would be 360 - 146 = 214 degrees, which is also impossible for a minor arc.
Let's assume 146° is the measure of arc BC. And 68° is the measure of arc CD.
Let the angle subtended by arc AC at the circumference be y. Then y = (arc AB + arc BC)/2.
Let the angle subtended by arc AD at the circumference be x. Then x = arc AD / 2.
We know arc AB + arc AD = 146°.
If we assume y and x are angles as shown in the diagram:
y is angle ABC. It subtends arc AC. So arc AC = 2y.
x is angle ABD. It subtends arc AD. So arc AD = 2x.
We are given arc BC = 146° and arc CD = 68°.
Arc AC = arc AB + arc BC = arc AB + 146°. So, 2y = arc AB + 146°.
Arc AB + arc BC + arc CD + arc DA = 360°.
arc AB + 146° + 68° + 2x = 360°.
arc AB + 2x + 214° = 360°.
arc AB + 2x = 146°.
We have two equations with three unknowns (arc AB, y, x):
1) 2y = arc AB + 146°
2) arc AB + 2x = 146°
This still doesn't give a unique solution.
Let's consider the possibility that y and x are directly related to the given arc measures.
If y is the inscribed angle subtending arc AC, and 146° is arc BC, and 68° is arc CD.
Let's look at the positioning of 'y' and 'x'. 'y' is inside angle ABC. 'x' is inside angle ABD.
Let's assume y is the measure of arc AB. And x is the measure of arc AD.
Then arc AB = y, arc AD = x.
We know arc AB + arc BC + arc CD + arc DA = 360°.
y + 146° + 68° + x = 360°.
y + x + 214° = 360°.
y + x = 146°.
This is the same equation as before. We still need more information.
Let's assume y and x are inscribed angles.
Angle ABC = y. It subtends arc AC. Arc AC = arc AB + arc BC.
Angle ADC = 146°. This seems to be an arc measure.
Angle ACD = 68°. This is an inscribed angle. It subtends arc AD. So, arc AD = 2 * 68° = 136°.
If arc AD = 136°, then from arc AB + arc AD = 146°, we get arc AB = 146° - 136° = 10°.
Now let's find y. Angle ABC = y subtends arc AC. Arc AC = arc AB + arc BC = 10° + 146° = 156°. So, y = 156° / 2 = 78°.
Let's check if this is consistent.
Arc AB = 10°, Arc BC = 146°, Arc CD = ?, Arc DA = 136°. Sum = 10 + 146 + ? + 136 = 360. 292 + ? = 360. ? = 68°. This matches the labeled arc CD = 68°.
So, we have:
Arc AB = 10°.
Arc BC = 146°.
Arc CD = 68°.
Arc DA = 136°.
y = Angle ABC = Arc AC / 2 = (Arc AB + Arc BC) / 2 = (10° + 146°) / 2 = 156° / 2 = 78°.
x = Angle ABD = Arc AD / 2 = 136° / 2 = 68°.
Let's verify the labeling. 'y' is placed at angle ABC. 'x' is placed at angle ABD.