Question

Morning. I'm needing to check some of my son's test answers. Solve for s. show all steps. -3s is greater than or equal to 18.....he put -3(-6) is greater than or equal to 18...so s is greater than or equal to -6

Answer 1

\[-3s \ge 18\] Divide both sides by -3 (so flip inequality):
\[s\le -6\]
He needs to remember to flip the inequality sign whenever he multiplies/divides by a negative number.

Answer 2

s has to be smaller than -6. like -7 is smaller than -6. Rest is correct.

Answer 3

ok. Thanks

Answer 4

@cgliss if you want to explain to him why this happens, give him the example of -1<5.
If you multiply both sides by -1 without swapping the inequality sign around, you get 1<-5. This doesn't make sense, so you have to flip it to 1>-5.

Answer 5

great example.....thanks