14r12s15 ÷ − 28r10s20
=
14r12s15
/
− 28r10s20
=
− 1
/
2
r12
/
r10
s15
/
s20
=
− 1
/
2
r2
s15
/
s20
=
− 1
/
2
r2
1
/
s5
=
−r2
/
2s5
| Step by step working:
−14
/
28
r12
/
r10
s15
/
s20
[Simplify constant term]
−141
/
282
=
− 1
/
2
[Simplifying r terms]
r12
/
r10
= r 12 − 10 = r2
[Simplifying s terms]
s15
/
s20
= s 15 − 20 =
1
/
s5
∴
14r12s15
/
− 28r10s20
=
−r2
/
2s5
|