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30 votes
Pls help ;-;
Solve for m∠B and m∠C in the parallelogram.

m∠B = ?°
m∠C = ?°

Pls help ;-; Solve for m∠B and m∠C in the parallelogram. m∠B = ?° m∠C = ?°-example-1
User Kausik Chat
by
2.6k points

2 Answers

13 votes
13 votes

Answer:

m∠B = 121

m∠C = 59

Explanation:

Angle B:


(10x - 19) = (7x+23)\\10x+(- 19+19) = 7x+(23+19)\\10x=7x+42\\(10x-7x) = (7x-7x)+42\\3x = 42\\3x/3 = 42/3\\x = 14

10(14)-19 = 140-19 = 121

Angle C:

(121)2 = 242

360-242 = 118

118/2 = 59

User Tabaluga
by
3.1k points
20 votes
20 votes

Answer:

  • 121° and 59°

Explanation:

Opposite angles of the parallelogram are congruent:

  • m∠B = m∠D
  • 10x - 19 = 7x + 23
  • 10x - 7x = 23 + 19
  • 3x = 42
  • x = 14

Find the angle B:

  • m∠B = 10*14 - 19 = 121°

Adjacent angles of the parallelogram are supplementary:

  • m∠B + m∠C = 180°
  • 121° + m∠C = 180°
  • m∠C = 180° - 121°
  • m∠C = 59°
User Page COW
by
3.1k points