6 ACT Math Formulas You MUST KNOW

In this video, Magoosh's ACT expert Kristin Fracchia goes over the six math formulas that you absolutely have to know for the ACT! Unlike the SAT, the ACT does not give you a list of formulas at the beginning of the math test. That means there are some you absolutely need to have memorized. Here are the more common ones that you might be called upon to use that you should definitely know by heart.
00:00 - Kristin introduces ACT math formulas
00:28 - Averages
01:38 - Slope
03:00 - Circumference of a circle / area of a circle
04:00 - Volume of a cylinder
04:41 - SOH - CAH - TOA
If you like a list of ALL of the math formulas you'll need to know for the ACT, check out the following blog post: magoosh.com/hs/act/2015/math-...
SUBSCRIBE to our channel for the best tips, tricks, and insights for acing the SAT and ACT tests as well as expert advice on getting into your school of choice.
Want more [SAT/ACT/College Admissions] tips? Check out these other videos from the Magoosh High School channel:
- ACT Math: Complex Imaginary Numbers: • ACT Math: Complex Imag...
- ACT Math Tips | Logarithm Strategies: • ACT Math Tips | Logari...
Got a test coming up? Check out our score guarantee and study with us: sat.magoosh.com/ or act.magoosh.com/
Join the Magoosh email list for 20% discount on your test: promotions.lpage.co/campaigns...
Did you know Magoosh has a blog? If you need more help, get deep insights and helpful advice there as well. Here are a couple posts to check out:
- ACT Math: How to Solve Probability Problems: magoosh.com/hs/act/act-math-p...
- ACT Math: How to Solve Circle Problems: magoosh.com/hs/act/act-math-h...
~-~~-~~~-~~-~
Check out our latest video: "ACT Science: 3 Strategies for Conflicting Viewpoints Questions"
• ACT Science: 3 Strateg...
~-~~-~~~-~~-~

[@lindaduong6371]

Formulas:
sum = average * (number of things)
slope = (y2-y1)/(x2-x1)
y=mx+b
circumference = 2pir
area = pir^2
volume of cylinder = hpir^2
SOH CAH TOA
3-4-5 triangle

[@a.marentes9337]

Linda Duong not all hero's wear capes...

[@totallyreal8878]

Thanks!

[@livlife8211]

If your allowed to use a graphing calculator you can go into program and make notes and write down the equations

[@GillAgainsIsland12]

You left out a whole bunch of important ones. But it was better than nothing. Here's one they must know: the equation of a circle: (x-h)^2 + (y-K)^2 = r^2, where (h,k) are the coordinates of the center point.

[@izvarzone]

bounding box/2 for x and y wouldn't be easier to find center?

[@isabellalove725]

If school was this simple I wouldn't have a hard time staying in school for explaining a topic over and over for so many days.

[@halnic3386]

I'm watching this before I go to take my test. Thank you so much!

[@sun.sh.in.e]

Haley Devers how did you do?

[@thinkvibrant5721]

This was great! Thanks for sharing ways to remember also the volume of a sphere is probably worth memorizing!

[@indianaadventuretourguide3394]

Thank you!

[@thatchickhannah6893]

I wish you would run through and do an example problem :( I still don’t understand anything

[@SilverMiraii]

One important formula I use all the time
old quantity/100 = new quantity/x , where x will give you the percentage change
and of course you can substitute anything in any place of this equation and you'll get the answer for what you're solving, maybe you wanna find the new quantity given a percentage change
500/100 = x/20 x here will give you 20 percent from 500
equivalent to 500*0.2
Here's another useful thing, SOH CAH TOA, it's a mnemonic for remembering basic trig identities sin cos and tan.
And the way I remember the circumference of a circle is by the definition of pi.
pi is defined to be the circumference divided by the diameter c/d=pi, and with simple algebra you can get it in any form.

[@bholakumarrampurtilak4512]

Thanks

[@monsoon1747]

I took my ACT today and none of these formulas came

[@libanabdullahi4435]

Monsoon 1 how much you got

[@orion8829]

Yeah… probably because you couldn’t recognize when you needed them

[@inmyopinion651]

Most kids that score poorly but have high GPAs is just lack of study time. Alot of kids won't put the 80 to 100 hours prep time in.

[@danforden9159]

exactly, i have like a 4.48 GPA but a 27 on the ACT...

[@josephquinto5812]

Or they go to very easy high schools.

[@paigereese4688]

Some people are also terrible at standardized tests. I have a high gpa and have worked very hard every day to raise my tests scores but it is still not as good as I would like it to be, I just get stressed out will taking standardized tests and fail to do as well I’m expected to with my gpa

[@yahyahassan4165]

Love you

[@lizettepecina997]

Saturday squad anyone?

[@haleymarie2906]

With slope does it matter if you have x2-X1 over y2-y1?

[@tanmarcus10]

+Haley Marie yes you have to have y^2-y^1 over x^2-x^1

[@solidaritytime3650]

Haley Marie yes. It must be "rise (y) over run (x)"

[@wormz7z900]

I’m taking the act tomorrow some of these I didn’t learn pray for me

[@undeadman7676]

For area, just think squarea. Easy peasy, one and done.

[@snipernosnipey8162]

Instead of 2(pi)r you should do (pi)d

[@titaniumsouls]

DontMessUA-cam //Clash Royale it's simpler to do 2(pi)r because it is the anti-derivative of the circumference, (pi)r^2
Just makes more sense to us calculus types

[@greenapple6404]

Lol SOHCAHTOA's are Algebra 1.

[@venturamack]

smart girls are pretty

[@ivands7249]

Your awesome! can I marry you? lol

[@solidaritytime3650]

The Musician Channel maybe if you spelled "you're" correctly...

[@2MinuteRatio]

Andddd...she has a ring...

[@Firebolt4]

Thanks