Help me please calc problem

Question

A plane flies 1.4 hours at 120 mph on a bearing of 10 degrees. It then turns and flies 7.9 hours at the same speed on a bearing of 100 degrees . How far is the plane from its starting​ point?

Answer 1

100-10=90 degrees change of direction

1.4(120)= 168 miles for one leg of the right triangle

7.9(120) = 84 miles for the other jeg

it's a 1-2-sqr5 right triangle

or 84-168-84sqr5 right triangle

hypotenuse = sqr(84^2 + 168^2)

= 84sqr5=about 187.8297101 miles

= about 188 miles from starting point

this looks more like a trigonometry problem than a calculus one