Question 47594
45/X+.5=70/(X+5) OR (45+.5X)/X=70/(X+5) OR 70X=45X+.5X~2+225+2.5X OR

.5X~2-22.5X+225=O OR X~2-45X+450)OR (X-15)(X-30)=0 OR X=15 & X=30 

PROOF 45/15+.5=70/(15+5) OR 3+.5=3.5 OR 3.5=3.5

SMITHS SPEED WAS 15 MPH & JONES WAS 15+5=20 MPH.