38.9k views
18 votes
Help i really dont understand this :')

btw its X + 15 not 25 i messed up

Help i really dont understand this :') btw its X + 15 not 25 i messed up-example-1
User Hosjay
by
6.5k points

2 Answers

12 votes

Answer:

See below ↓↓↓

Explanation:

  • ∠ABC and ∠CBD are complementary
  • ⇒ ∠ABC + ∠CBD = 90°
  • ⇒ 4x + 25 + x + 15 = 90
  • ⇒ 5x + 40 = 90
  • ⇒ 5x = 50
  • x = 10

  • ∠ABC = 4x + 25
  • ∠ABC = 4(10) + 25
  • ∠ABC = 65°

  • ∠CBD = x + 15
  • ∠CBD = 10 + 15
  • ∠CBD = 25°
User Douarbou
by
7.3k points
4 votes

x = 10°

ABC = 65°

CBD = 25°

==============

Both the angles lie inside of right angle triangle whose interior angle sums up to total 90°

Solve for x :

  • 4(x) + 25 + x + 15° = 90°
  • 4(x) + x + 25 + 15 = 90°
  • 5(x) + 40° = 90°
  • 5(x) = 90° - 40°
  • 5(x) = 50°
  • x = 10°

====================

  • ABC = 4(x) + 25 = 4(10) + 25 = 65°
  • CBD = x + 15° = 10 + 15° = 25°
User Sachadso
by
7.6k points