Anthony B. answered • 11/10/15

Experienced Calculus Tutor

1. let's use the law of cosines for this :)

2. let a = 70 and b = 175

3. also, 21° is the angle that is opposite to the side of the triangle that we are looking for

4. the law of cosines = c

^{2}= a^{2 }+ b^{2}- 2*a*b*cos(21°)5. substitute the values in: c

^{2}= (70)^{2}+ (175)^{2}- 2*70*175*cos(21°)6. c

^{2}≈ 12652.2807. c ≈ ±√12652.280 ≈ ±112.482

8. since we're dealing with the magnitude of a displacement vector, we take the absolute value of ±112.482, which is 112.482

9. therefore, she must fly ≈ 112 miles farther in order to reach Indianapolis