How do you solve compound inequalities $8d<-64$ and $5d > 25$ ?

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Answer 1 · 2015-05-19T08:10:52

Let's look at each inequality individually first.

$8d<-64$

Dividing both sides by 8, we get:

$(cancel(8)d)/cancel(8) < -64/8$

$color(blue)(d < - 8$

$5d>25$

Dividing both sides by 5, we get:

$(cancel(5)d)/cancel(5) > 25/5$

$color(blue)(d>5$

$d$ can take any value which is less than $-8$ or greater than $5$

The values $d$ will take on the number line are marked in blue. (The values $-8 and 5$ are not included)

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How do you solve compound inequalities 8d<-648d<-64 and 5d > 255d > 25?