Answer:
2.6 meters per second
Step-by-step explanation:
you divide 390 meters by 150 seconds
390/150= 2.6
r=-3, 3,0
factor -
3r(r-3) (r+3) ,
solution-
3r=0 , r=0
3r^2-9r =0
3r^2=9r
r=3,
r+3=0
r= -3
SSS conguent
hope it helps