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

2 Answers
Apr 24, 2018

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

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