Completing the Square

Learn how to Complete the Square in this free math video tutorial by Mario's Math Tutoring. Solving quadratic equations by completing the square. We go through a few different type of examples.

0:18 How to Find the c Value to Make the Trinomial a Perfect Square in the Example 1 x^2 + 10x + c
1:36 Example 2 Find c by Completing the Square in x^2 + 5x + c
2:06 How to Factor Once You Complete the Square
2:27 Example 3 Solve the Equation by Completing the Square in x^2 + 4x - 10 = 0
3:19 Take the Square Root of Both Sides and Write Both Answers
4:08 Example 4 More Challenging Example of Solving the Equation by Completing the Square for 3x^2 + 6x - 9 = 0

Related Videos:

Completing the Square to Solve Equations

Completing the Square (More Challenging) 2 Examples

Circle Equation and Completing the Square

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[MariosMathTutoring]

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- Mario

[yingweichen]

The best online maths tutoring ever! Great!

[fortimusprime]

Some people are truly talented to teach! This is simpler than I thought! I'm Pre-Calculus and needed a refresher! Thanks Mario! Keep up the great work!

[EngineermanCullen]

I'm in calculus 3 and needed a quick refresher on this! I will recommend this video to classmates!

[greenlink]

Practice makes perfect, especially for tests. Me studying right before a test on online school lol.

[larsongeneraletc....]

Eu sou moçambicano e você me ajudou, I'm so grateful

[EngineermanCullen]

Wow great video for a recap on this. Great job!

[kerriesposito]

Thank you! This is such a great video! I needed a refresher. You explain things so well and make them so easy to understand!

[osmanazhar]

Great Video! Needed some review for Calc 2 and this was perfect.

[aerdis]

Is mathematically wrong if you write that 10/2=5²

[lmj]

🎶

"completing the Square!
completing the Square...
half the x and put in brackets,
subtract the Square, of that
number there,
we have completed the
Square!"






😅

[sheluvdee]

who's here the day before the test??...lmao

[jaromluker]

Numerous mathematical inaccuracies in this video, most notably suggesting that square root is the inverse of square then applying a plus-or-minus after that, when the reality is that the square function across the real numbers has no inverse, because it is not a surjection. The plus-or-minus should be applied *with* the square root, not after... Also my personal pet peeve--using the mnemonic device, "FOIL", as a verb in place of the mathematically correct term, *distribute.*