Answer:
54.314 °
Explanation:
It is given that in triangle ABC, AB = AC = 6m. So, it is an isosceles triangle
Now, it is also given that BC = 7 cm.
We have to find the value of angle C.
If we draw a perpendicular on BC from point A, then it will bisect BC at D i.e. AD is a perpendicular bisector of BC.
Now, the triangle ADC is a right triangle in which, the base DC =7/2 =3.5 cm and hypotenuse AC = 6m (Given) and angle ADC= 90°.
Therefore, Cos∠C = DC/AC =3.5/6.
⇒ ∠C =Cos⁻¹ (3.5/6) =54.314 ° (Answer)