SAT Math Quadratic Equations Word Problem

#shorts

The test seems to ask about vertex a lot. I will try to tackle harder questions on the SAT math portion. It is a little difficult to try to explain it in under one minute. Hope the video helps.

[vigneshnatarajan]

If a line intersects a curve at one point, then the line and curve will have a common root, so plugging y=c in the parabola equation and making ∆=0 will also give the solution

[SladeMacGregor]

I must say, the formula x = -B/2A is a neat little formula. But the problem with x = -B/2A is that you hope to recall this formula on the test while under a lot of pressure. Memorizing formulas is a nightmare for me. With a lot of us, there are numerous formulas to memorize for the SAT, and I'm horrible at memorizing formulas! lol Sorry to pick on you, MethodMan. Anyway, I solved at y = 0, which shows two solutions for x, x=0 and x=5. Then I halved the distance between 0 & 5 which is x=5/2....then solve for y=c at the vertex. By the way, this is a fantastic problem to solve. Enjoyed it and Merry Christmas!

[NimishP]

Can’t we use derivative of the function to find the maximum value of the curve where dy/dx equals zero?

[fabianbotello]

All methods are valid, there is no correct way. Another way to get the answer is to complete the square so that you get in in the form of (x-a)^2+b and b is the vertical shift (answer) :)