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Fie ∆ABC dreptunghic,m(unghiului B)=90°.Punctul M este mijlocul ipotenuzei.Stiind ca m(unghiului A)=30°si MC =3,2cm.Aflati perimetrul∆BMC.Dau coroană!

1 Answer

5 votes

Answer:

Explanation:

MC = 4.5cm

Step-by-step explanation:

Question:

Let the isosceles triangle ABC with AB = AC = 3 cm. if the mediator of the sides AC intersects with the side BC in M ​​and the perimeter of the triangle AMC = 12 cm. Calculate MC.

Solution:

Find attached the diagram used in solving the question.

Given:

∆ABC is an isosceles triangle (two sides and angles are equal)

AB = BC = 3cm

Perimeter of ∆AMC = 12cm

From the diagram, M cuts AC at the the middle.

AD = CD = AC/2 = 3/2

Perimeter of Right angled ∆AMD = AM + AD + MD

= 3/2 + AM +MD

Perimeter of Right angled ∆CMD =CM + CD + MD

= 3/2 + CM +MD

Right angled ∆AMD = Right angled ∆CMD

CM = AM

Therefore ∆AMC is an isosceles triangle

CM = AM (two sides of an isosceles triangle are equal)

Let CM = AM = x

Perimeter of ∆AMC = AM + CM + AC

12 = x + x + 3

12 = 2x + 3

2x = 12-3

2x = 9

x = 9/2 = 4.5

CM = AM = 4.5cm

MC = CM = 4.5cm

User Zarick Lau
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