Well,
H<span>ope that helps!!</span>
Perpendicular means that the slopes are negartive inverses, aka
slope1 times slope2=-1
y=mx+b
slope=m
y=-1/2x-2
slope=-1/2
we need to find negative inverse
-1/2 times what=-1
answer is 2
y=2x+b
input the point (2,-2) to find b
(x,y)
(2,-2)
-2=2(2)+b
-2=4+b
minus 4 from both sides
-6=b
y=2x-6
the equtaion is y=2x-6
so notice above, the circle is centered at h,k or 0,0, the origin, and has a ratio of 5.
and y = 2, is just a horizontal line, check the picture below.
we know that
Applying the law of cosines:
c² = a² + b² - 2abcos(C)
where:
a,b and c are sides of the triangle and C is the angle opposite side c
let
a=170 mi
b=200 mi
c=160 mi
that is
160² = 170² + 200² - 2(170)(200)cos(C)
solve for C
25,600 = 28,900 + 40,000 - 68,000cos(C)
25,600 - 28,900 - 40,000 = -68,000cos(C)
-43,300=-68,000cos (C)
cos (C)=0.6367
C=arc cos(0.6367)--------> C=50.45°
hence,
he should turn in the direction of island b by
180 - 50.45 = 129.55 degrees
the answer is
129.55 degrees
