Digital SAT Math Crash Course - Day 1 (Part 2) - Taking Advantage of Demos... Continiued!

[@Abid.RK0]

43:42 For this problem, It would be much easier to type in the "a" with the 2nd equation in desmos. Which would allow you to pull up a slider in desmos for the value of a. Now, you can just drag the value and experiment with different numbers to find the value for. *** Note :- By default the value would only go upto 10, but if you click on it then you can set the limit to any value you desire**

[@MichaelToohey]

Dude!! I had no idea you could do that!! Thank you so much for sharing!! I’ll implement this with my students!! : )

[@aamna2110]

thank you so much!!! you seriously can't imagine what a big help these videos have been. not just in strengthening concepts, but also for increasing confidence whilst solving the questions themselves. the panic is the worst part in any kind of test.

[@MichaelToohey]

Thanks for reaching out!! I’m happy to help!! Yes, just knowing the rules is huge, and learning to apply them makes this the easiest section of the test to get a good score increase on… Let me know if you have any questions!!

[@MichaelToohey]

One more thing: focus on the ones you can answer for sure (applying the rules), and don’t drive yourself crazy about the highest level-of-difficulty questions!! That’s your path to finishing on time, with a good score increase! You can do this!! : )

[@OverclockingCowboy]

On Question 21 40:50, it is fun to play with the “slider” on Desmos. But this question can be answered quickly by just completing the square. x^2 + 8x + (a + 1.5) = (x + 4)^2 Equating the “c” terms, a + 1.5 = 16 a = 14.5

[@MichaelToohey]

Nicely done! I’m down with anything that works! Most students I work with aren’t too familiar with completing the square though, so I’m coaching the to go straight to Desmos on a question like this…

[@haniamalik6867]

waiting for part 2!!!

[@MichaelToohey]

Part 2 is published!! You can find it on my channel! : )

[@haniamalik6867]

​@@MichaelToohey I meant day 2 part 1 video

[@MichaelToohey]

@haniamalik6867 Ah! Gotcha! Makes sense… I’ll have Day 2 out as soon as possible! : )

[@haniamalik6867]

@@MichaelToohey thanku for being consistent

[@MichaelToohey]

@haniamalik6867 I’m doing my best! : )

[@reineie]

I want advice on this. I graduated a while ago, but I need to study the SAT now to be accepted into a certain university with another major. I am lost and I don’t know how to start. I barely remember anything about mathematics, especially since my previous major was arts, we didn't study anything related to mathematics unfortunately ‏. I didn’t know how to start.

[@MichaelToohey]

Thank you for reaching out to me!! I’ll be so happy to help!! And I can relate!! Before I started tutoring for the SAT/PSAT, I hadn’t been in a real math class in 17 years. I had forgotten how to do many of the basics. The good news, however, is that you don’t need very advanced math skills to do well on this test!! Heck, you don’t even need arithmetic, now that you can use the Desmos calculator all throughout the test!! Start by watching my Digital SAT Math Crash Course videos, all the way through… you’ll see you don’t need to know everything - just enough to find the right answer or get rid of the obviously incorrect answers. That’s it. It’s barely a math test: it’s more like a logic test with math principles. Watch my videos, and let me know if you have any questions… I’ll be happy t guide you through this process! And don’t worry! If you’re willing to put in the work (and I suspect you are) you have the ability to succeed on this test!

[@reineie]

@@MichaelToohey Although I do not have KZbin notifications, I saved the video in case you respond to my questions. Thank you for your response. I will start making a study plan and follow your advice, and if I have a question, I can ask you... Thank you very much again.🤍

[@MichaelToohey]

Happy to help!! Don’t hesitate to reach out!!

[@DaisyBells-st6nm]

Pls the number 23 that has circle is it 4 0r 8

[@MichaelToohey]

Good question!! The diameter is 8, answer choice B. The radius is 4, but that’s not what the question’s asking… It’s asking for the diameter. Make sense?

[@DaisyBells-st6nm]

@@MichaelToohey yes thank you😌

[@DaisyBells-st6nm]

Sir I'm still confused with that -x2-bx-676 question why is it 51 isn't the point not meant to pass after the line?

[@MichaelToohey]

Good question!! We’re looking for the largest value of b that doesn’t cross (or touch) the x-axis… that’s because if it touches the x-axis that indicates a solution to the equation… notice that when we plugged in a 52 for b, the parabola touched the x-axis at one point: that indicates ONE solution to the equation. It doesn’t have to cross the x-axis to be a solution - just touching it is enough. So the biggest value of b that give us no solution (that is, doesn’t touch or cross the x-axis) is indeed 51. Make sense?

[@DaisyBells-st6nm]

@@MichaelToohey yes a bit

[@MichaelToohey]

@DaisyBells-st6nm Also, remember the solutions to the equation are points that cross the x-axis, not the y-axis.

[@OverclockingCowboy]

If you are still confused, just calculate the determinant: Determinant = (b)(b) - 4(676) If determinant equals zero, you get one solution. If less than zero, no solution. If more than zero, 2 solutions. You set the determinant to zero in order to compute the value of b. You will get b = +/- 52. Note the plus and minus. The greatest positive integer for b is 51 for no solution. GRAPHICAL INTERPRETATION The parabola can face upward or downward. The sign of the coefficient of x^2 gives you this information. In this case we have a downward parabola (negative). When the vertex of the parabola touches the X axis, you have one solution. It means that the determinant equals zero. When the vertex crosses the X axis, you have 2 solutions due to the symmetry of the curve. It also means that the determinant is greater than zero. When the vertex does not touch or cross the X axis, you have no solution. Determinant is less than zero.

[@MichaelToohey]

That works too!