122k views
1 vote
In parallelogram ABCD, angles A and C are opposite angles with the measure of angle A as 7x+8 and the measure of angle C as 10x-22. What is the measure of angle B? Answer as a decimal rounded to the nearest hundredth if not a decimal.

Your Answer:

User Otterfan
by
7.3k points

1 Answer

4 votes

Final answer:

The measure of angle B in parallelogram ABCD, using the given expressions for angles A and C, is found to be 102 degrees after solving for x and using the properties of a parallelogram.

Step-by-step explanation:

In parallelogram ABCD, we know that opposite angles are congruent, meaning that the measure of angle A is equal to the measure of angle C. We are given that the measure of angle A is 7x+8 and the measure of angle C is 10x-22. Since angles A and C are congruent, we can set their measures equal to each other to find the value of x:

  1. 7x + 8 = 10x - 22
  2. Subtract 7x from both sides: 8 = 3x - 22
  3. Add 22 to both sides: 30 = 3x
  4. Divide by 3: x = 10

Now that we have the value of x, we can find the measure of angle A or C by substituting x back into either equation:

  • Measure of angle A = 7(10) + 8 = 70 + 8 = 78
  • Measure of angle C = 10(10) - 22 = 100 - 22 = 78

Because angle B is adjacent to angle A in a parallelogram, angle B and angle A are supplementary, meaning their measures add up to 180 degrees:

  • Measure of angle B = 180 - Measure of angle A
  • Measure of angle B = 180 - 78 = 102
User Raynita
by
7.6k points