11. D=rt for r
Divide both sides by t
D/t=r
12. F=v+at for v
Subtract at from both sides
f-at=v
13.AX+BY=c. For x
Subtract BY from both sides
AX=C-BY
divide both sides by A
X=c-BY/A
14.A=1/2 Pl
Multiply both sides by 2
2A=Pl. for l
Divide both sides by P
2A/I = P