How do you solve #m/-7< 1.2#?

1 Answer
Apr 17, 2016

Answer:

To solve this you would multiply both sides of the equation by -7 and change the #<# sign to# >#.

Explanation:

When solving #m/(-7) < 1.2# it is important to remember that
if you multiply or divide by a negative number then the greater than or less than sign must be flipped.

Method 1

Multiply each side by #-7# and flip the sign.

#(-7)m/(-7)<1.2(-7)#

#m > -8.4#

Method 2

To solve without multiplying by a negative:

Multiply each side by 7:
#(7)(m)/(-7)<1.2 (7)#

#-m<8.4#

Subtract #-m# from each side of the inequality.
#0<-m+8.4#

Subtract -8.4 from each side of the inequality.
#-8.4 < m#

which is the same as
#m > -8.4#

Check

Pick a value for #m# and substitute it into the original inequality.
Since #0# is greater than #-8.4# we can use that to test our answer.

#m/(-7)<1.2 #

#0/(-7)<1.2 #

#0<1.2#

Since this is a true statement our problem checks.