Speed question

[trailblaza247]

Homework Statement

dan is gliding on his sb at 4m/s. he suddenly jumps backward off his sb, kicking the sb foward at 8m/s. how fast is dan going as his feet hit the ground? dan's mass is 50kg and the sb's mass is 5kg

Homework Equations

The Attempt at a Solution

 

[mbrmbrg]

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