Asked by Cheezel
Solve the equation 5x^2-5x-63=0 by using the "complete the square" method. Give your answer to 2 decimal place.
Please show me in clear steps how to get the answers 4.08 and -3.08.
Please show me in clear steps how to get the answers 4.08 and -3.08.
Answers
Answered by
Steve
5x^2-5x-63
= 5(x^2-x) - 63
Recall that (x-a)^2 = a^2-2a+a^2
Here we have 2a = 1, so a = 1/2. So, add and subtract 1/4 * 5
= 5(x^2-x + 1/4) - 63 - 5/4
= 5(x - 1/2)^2 - 267/4
To get the roots, set that to zero:
5(x - 1/2)^2 - 257/4 = 0
5(x - 1/2)^2 = 257/4
(x - 1/2)^2 = 257/20
x - 1/2 = ±√(257/20)
x = 1/2 ±√(257/20)
x = -3.08 or 4.08
= 5(x^2-x) - 63
Recall that (x-a)^2 = a^2-2a+a^2
Here we have 2a = 1, so a = 1/2. So, add and subtract 1/4 * 5
= 5(x^2-x + 1/4) - 63 - 5/4
= 5(x - 1/2)^2 - 267/4
To get the roots, set that to zero:
5(x - 1/2)^2 - 257/4 = 0
5(x - 1/2)^2 = 257/4
(x - 1/2)^2 = 257/20
x - 1/2 = ±√(257/20)
x = 1/2 ±√(257/20)
x = -3.08 or 4.08
Answered by
Anonymous
xy=90
2x+y=36
2x+y=36
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.