I would like some help wit problems like #19.
The story tells us he is starting with 10 words. Think of this as the starting point. EACH day 2 new words will be added...this is going to have the variable. So learning words can be shown as 2x + 10 (2 words per day, plus the 10 already mastered).
If he wants AT LEAST 75 words, he wants 75 words...or more! This means we want our amount to be greater than or equal to 75. This can be shown as 2x + 10 > (or equal) 75.
Now just solve like a normal inequality! 2x > 65, x > 32.5...but since we won't have half a day, on day 33 he will have at least 75 words. Hope this helps!