Its D
Its the only one that makes since
A^2 = b^2 + c^2 - 2bc cos a
= 11^2 + 5^2 - 2*5*11 cos 40
= 7.86 to 2 DP's
to find the remaining angles use the sine rule:-
a / sin A = b / sin B so
7.857/ sin 40 = 11 / sin B
sin B = 11 sin40 / 7.857 = 0.8999
<B = 64 degrees
so <C = 180 - 64-40 = 76 degrees
an equilateral triangle has a square root height if 3 so I'm guessing if you multiply square root of 3 times 8
Use Pythagoras theorem
Hypotenuse²=Base²+ Height ²
H²=(8)²+(6)²
H²=64+36
H²= 910
H²=10√91 cm Solution
(15, -8) :)
From C to midpoint you do (+10, -7), so you have to do that again to get to D
