-3 ≤ 1-5x ≤ 7
We solve for x in the middle:
Add -1 to all three sides like this:
(Or you may say "Subtract 1 from them"):
-3 ≤ 1-5x ≤ 7
-1 -1 -1
-------------
-4 ≤ -5x ≤ 6
Now that you have
-4 ≤ -5x ≤ 6
Divide all three sides by -5.
However when we divide an inequality by
any negative number we always must reverse
the direction of the inequalities, so we get
or
Sometimes people prefer to leave answers with
instead of , because they like to think left
to right on the number line, So we might better write
that as:
[Just remember that
LARGE > MEDIUM > SMALL
is equivalent to
SMALL < MEDIUM < LARGE
Edwin