Question

CAN YOU SOLVE PLEASE. ..... ​

Answer 1

Answer:

Step-by-step explanation:

Let the speed be 'x'

Then t(1)=1200/x

t(2)=1200/(x+60)

t(1)-t(2)=1

1200/x - 1200/(x+60)=1

By cross multiplication,

1200x+7200-1200x/x^2+60x=1

x^2+60x=7200

x^2+60x-7200=0

x^2+60x-120x-7200

x(x+60)-120(x+60)

(x-120)(x+60)

Speed cannot be negative

Therefore,speed=120km/hr