#7-8x >19-7# please answer this on how to solve the inequality?

2 Answers
Apr 24, 2018

Answer:

#x < -5/8#

Explanation:

Isolate x.

#7 - 8x > 19 - 7 #

Add #7# to #-7# to cancel it out because it is the lowest number here.

But you do to one side what you do to the other, so add #7# to the positive #7# on the other side. You should now have:

#14 - 8x > 19#

Now, subtract #14# from #14# to cancel it out and do the same to the other side #(19)#. Now, you should have:

#-8x > 5 #

Now, to isolate #x,# divide by #-8#.

But remember when you divide or multiply an inequality by a negative value, the sign changes around.

#(-8x) /( -8) < 5/(-8)#

Because you divided by a negative, the sign flips:

#x < -5/8#

Apr 24, 2018

Answer:

#x <-5/8#

Explanation:

You can treat an inequality in exactly the same way as an equation, except if you multiply or divide by a negative value, the inequality sign changes around.

#7color(blue)(-8x)>19-7#

Let's avoid the problem with a negative term with the variable by moving it to the other side,

Add #8x# to both sides and simplify where possible:

#7cancel(-8x) cancel(+8x)>12color(blue)(+8x)#

Subtract #12# from both sides:

#7-12 >12+8x-12#

#-5 > 8x#

#-5/8 > x" "larr (div 8# on both sides)

This can be written as #x <-5/8#