Question

an aeroplane at an altitude of 250m observes the angle of depression of two boats on opposite banks of a river to be 45 and 60 degrees respectively. find the width of the river . write the answer correct to nearest whole number

Answer 1

From the figure attached
B1 = Boat 1
B2 = Boat 2

tan 60 = OB2/250
OB2 = 250 tan 60 = 250 x 1.732 = 433 m

tan 45 = OB1/250
OB1 = 250 tan 45 =  250 x 1 = 250

Width of the river = OB2 - OB1
                             = 433 -  250
                             = 183m

Answer 2

Answer:

393

Step-by-step explanation:

tan 45=h/b

1=h/b

1=25

b

b=250

tan 0=h/b

√3=50/b

b=20/√3

eq 1 & 2

250+250/√3

250+250/√3×√3

/√3

250+83×√3

250+83×1.732

50+143.7

393.7

I Hope it will help u