how to solve this problem

First distribute the 2 into the (6x - 13):

14x - 18 < 12x - 26

Now subtract 12x from both sides to get all the terms with an x on the same side of the inequality:

14x - 18 - 12x < 12x - 26 - 12x

Combine the terms with x's:

2x - 18 < -26

Add 18 to both sides to get all the constant terms on the other side of the inequality:

2x - 18 + 18 < -26 + 18

Combine the constant terms:

2x < -8

Divide both sides by 2 to get x completely by itself on the left side:

(2x)/2 < (-8)/2

Reduce both sides and you end up with:

x < -4