Friday

April 18, 2014

April 18, 2014

Posted by **Pooja** on Wednesday, August 10, 2011 at 5:30am.

- geometry -
**Reiny**, Wednesday, August 10, 2011 at 8:17amSince AD is the median

BD = DC = 9

In ∆ABD, let ∢BDA = Ų

by the cosine law:

8^2 = 9^2 + 7^2 - 2(9)(7)cosŲ

cosŲ = .5238

Ų = 58.4°

the ∢ADC = 121.59°

now in ∆ADC

AC^2 = 49 + 64 - 2(7)(8)cos121.59

= 171.666667

AC = 13.102 or 13

**Related Questions**

Maths - triangle ABC is right angled at A. AD is perpendicularto BC. If AB= 5cm,...

geometry - AD is an altitude of an isosceles triangle ABC in which AB=AC. Show ...

geometry proofs - given ABC is a triangle. Ad is the altitude to BC. Ad biscects...

Maths - Triangle ABCis right angled at a .AD is perpendicular to BC.If AB=5cm,BC...

MATHS,7TH CLASS - A RIGHT ANGLED TRIANGLE ABC IS GIVEN,WHERE AB IS 5CM,AC IS ...

Geometry - ABC is a triangle with circumcenter O , obtuse angle BAC and AB<AC...

Geometry - ABC is a triangle with circumcenter O , obtuse angle BAC and AB<AC...

geometry - in right triangle ABC, the altitude CD is drawn to hypotynuse AB. The...

geometry - ABC is a triangle with AC=139 and BC=178. Points D and E are the ...

Geometry - Please answer at least one . PLEASE 1. Triangle XYZ has a right ...