42 < –6d

solve it just as you would an equation:

42 = -6d
-7 = d

However, multiplying and dividing by negative values changes the direction of the inequality. So, you have

42 < -6d
7 < -d
-7 > d or d < -7

Since you can always add and subtract without changing the direction, the direction-switch is just a shorthand way to move items from one side to the other:

42 < -6d
42+6d < 0
6d < -42
d < -7

post it.

To solve this inequality, you need to isolate the variable "d" on one side of the inequality symbol.

42 < -6d

First, divide both sides by -6 to isolate "d" by itself:
42 / -6 < -6d / -6

This simplifies to:
-7 < d

So the correct answer is A. d < -7.

Explanation:
When you divide or multiply both sides of an inequality by a negative number, you need to flip the inequality symbol. In this case, you divided both sides by -6, which is negative, so you flipped the inequality. That's why -7 is the greater value.