Find the slope and the y-intercept line

y=2/3x (note 2/3 is a fraction, 2 over 3)

slope:
y-intercept:

Step-by-step explanation:

slope=2/3

y=2/3 x

or y=2/3 x+0

y -intercept=0

since the airplane is moving with constant speed then the distance travelled can be calculated by x=u*t

in km/h would be:

x=640*3.5=2.240 km

in m/s would be:

u=640 km/h= 640.000 m/h =640.000/ 3600 m/s =177.8 m/s

t= 3.5 h= 3.5 * 3600 s=12.600 s

then x=u*t= 177.8*12.600= 2.240.280 m