Answer:
4
Step-by-step explanation:
Answer:
∠A= 45°....
Step-by-step explanation:
To find ∠A first we have to find the length of side B by cosine law:
b^2 = a^2 + c^2 – 2 a c cos B
b^2=(2)^2 +(√3 + 1)^2 - 2(2)(√3 + 1) cos 60
b^2 = 6
Taking square root at both sides:
√b^2 = √6
b= 2.45
Now we can calculate ∠A by sine law:
b / sin B = a / sin A
2.45 / sin 60 = 2 / sin A
sin A= 2* √3/2 /2.45
sin A = 2√3/2 * 1/2.45
sinA = 2√3/ 4.9
sin A = 0.7069
sin A = 0.707
A=45°
Thus ∠A= 45°....
See attached. The trick is to use similar triangles.
