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Please I need help on question 7​

Please I need help on question 7​-example-1
User Eugen Timm
by
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1 Answer

5 votes

Answer:

x = 90

y = 30°

∠ABC = 75°

Explanation:

Finding the angles of isosceles triangle:

ΔDAB is an isosceles triangle.

⇒ ∠ADB ≅ ∠ABD = y

In ΔABD ,

120 + y + y = 180 {Angle sum property of triangle}

120 + 2y = 180

2y = 180 - 120

2y = 60

y = 60 ÷ 2


\sf \boxed{y = 30^\circ}

ΔDCB is an isosceles triangle.

∠CDB ≅ ∠CBD = 45

x + 45 + 45 = 180

x + 90 = 180

x = 180 - 90


\sf \boxed{x = 90^\circ}

∠ABC = ∠ABD + ∠DBC

= 30 + 45

= 75°

User Seamus Leahy
by
2.8k points