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anonymous
 one year ago
How do you complete the square to form perfect trinomial for 4x^2=14x+8
anonymous
 one year ago
How do you complete the square to form perfect trinomial for 4x^2=14x+8

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0How did you do it tho steps pleases

anonymous
 one year ago
Best ResponseYou've already chosen the best response.01 Move all terms to one side 4x2−14x−8=0 2 Factor out the common term 2 2(2x2−7x−4)=0 3 Factor 2x2−7x−4 1. Multiply 2 by 4, which is 8. 2. Ask: Which two numbers add up to 7 and multiply to 8? 3. Answer: 1 and 8 4. Rewrite −7x as the sum of x and −8x: 2(2x2+x−8x−4)=0 4 Factor out common terms in the first two terms, then in the last two terms 2(x(2x+1)−4(2x+1))=0 5 Factor out the common term 2x+1 2(2x+1)(x−4)=0 6 Solve for x 1. Ask: When will (2x+1)(x−4) equal zero? 2. Answer: When 2x+1=0 or x−4=0. 3. Solve each of the 2 equations above: x=−12,4

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0fan and medal please

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0fan me, go to my name and something will come and it says 'become a fan', and click that

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thanks lol can you also help me with others?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Also on the first one how did you get 12,4 but you said it's 4,1/2

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0He got 1/2 and 4. He just forgot to write the / between the 1 and the 2.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ohh okay thank you!!

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0Do you just need to solve the equation using any method, or do you have to use the complete the square method?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0it just says complete the square to form a perfect square trinomial

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0Then you need to complete the square. This is how you complete the square to solve a quadratic equation. I'll show you the steps.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0thank your a life saver!

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0Your equation is: \(4x^2=14x+8\) 1. You need the x^2 term and the x term to the left side, and the number on the right side. All we need to do is subtract 14x from both sides. \(4x^2  14x = 8\)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0wait so idont have to have the 4,1/2

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.02. The first term must be just x^2 (without a coefficient). If it is not, then divide both sides of the equation by the coefficient of the x^2 term. In our case, we divide the equation by 4 on both sides to get: \(\dfrac{4}{4}x^2  \dfrac{14}{4}x = \dfrac{8}{4} \) which simplifies to \(x^2  \dfrac{7}{2}x = 2 \) As you can see, we now have just x^2 for the x^2 term.

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.04 and 1/2 are the solutions of the equation. If we complete the square and continue, we will get to 4 and 1/2. You'll see.

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0Now we are just completing the square.

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0We are ready for the next step. This is the actual step that completes the square.

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.03. Take half of the coefficient of the xterm, and square it. Add it to both sides. \(x^2  \dfrac{7}{2}x = 2 \) Half of 7/4 is 7/4. The square of 7/4 is 49/16. We add 49/16 to both sides. \(x^2  \dfrac{7}{2}x + \dfrac{49}{16} = 2 + \dfrac{49}{16} \) Now we write the left side as the square of a binomial, and we add the fractions on the right side.

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0\(\left(x  \dfrac{7}{4} \right)^2 = \dfrac{32}{16} + \dfrac{49}{16} \) \(\left(x  \dfrac{7}{4} \right)^2 = \dfrac{81}{16} \) Ok, the complete the square step is finished.

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0If all you need to do is complete the square, you are done now.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0is that a perfect square trinomial?

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0Yes. The left side is a perfect square trinomial when written as \(x^2  \dfrac{7}{2}x + \dfrac{49}{16} \)

mathstudent55
 one year ago
Best ResponseYou've already chosen the best response.0Once you complete the square, you can solve the quadratic equation. Take square roots of both sides: \(\sqrt{\left(x  \dfrac{7}{4} \right)^2} = \pm \sqrt{\dfrac{81}{16}} \) \(x  \dfrac{7}{4} = \pm\dfrac{9}{4} \) Now separate the equation into two equations: \(x  \dfrac{7}{4} = \dfrac{9}{4} \) or \(x  \dfrac{7}{4} = \dfrac{9}{4} \) \(x = \dfrac{9}{4} + \dfrac{7}{4} \) or \(x =  \dfrac{9}{4} +\dfrac{7}{4} \) \(x = \dfrac{16}{4} \) or \(x =  \dfrac{2}{4}\) \(x = 4\) or \(x = \dfrac{1}{2} \) As you can see, we get x = 4 or x = 1/2, as you had gotten before.
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