Answer:
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
