Question

q.no.15 of ncert class 10th ex.9.1 ....my younger sister is asking this to me give me sol.as soon as possible...

Answer 1

see pic..............

Answer 2

Let the uniform speed of car =a m/sec
angle 1=30' angle 2=45
time taken by car from A to B=6sec
distance from A to B= speed×time = 9x
in triangle BCD tan60=p/b
root3= h/ax
h=root3ax
in triangle ACD tan30= h/ 6a+ax
1/root 3= h/6a+ax
6a+ax=root 3h
6a+ax = root3 (root3 ax)
6a+ax=3ax
6a+ax-3ax=0
6a-2ax=0
6a= 2ax