text: how do you use algebra in everyday life?   actually, if you get really good in algebra, you can use that skill to do arithmetic better in the real world. you can do things in your head instead of on paper.  here's a really simple example: let's say that you want to buy three of something that costs $18.  off the top of your head, you don't know what 3 x 18 is.  but! algebra tells you that multiplication is associative.  so if you think of 18 as 2x9, then you can think:  3 x 18 = 3 x (2 x 9) = (3 x 2) x 9 (that's the associative part) = 6 x 9 and then you remember from your multiplication tables that 6 x 9 is 54.  so you'll pay $54.  here's a more complicated example: you're traveling for 5.5 hours at 65 miles per hour, and want to know how much distance you'll cover (distance = speed x time).  well, first, 65 x 5.5 = 65 x (55 / 10) = (65 x 55) / 10.  but now, how do you multiply 65 x 55 in your head?  well, if you've learned about factoring in your algebra class, you can reason based on the "difference of two squares":  (a+b)(a-b)=a² - b²  65 x 55 = (60 + 5)(60 - 5) = 60² - 5² (there's the difference of two squares factoring coming into play) = 3600 - 25 (60 and 5 are easy to square in your head) = 3575 (also easy)  so 65 x 5.5 = 3575 / 10 = 357.5 miles!  and the point is that, with the algebra knowledge, you can do a lot of this in your head -- i wrote it all out for you to read, but you don't have to!