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6 votes
6 votes
Some of the steps for completing the square to solve

x2 + 5x = 2 are shown.


x2 + 5x = 2


x2 + 5x + (StartFraction 5 Over 2 EndFraction) squared = 2 + (StartFraction 5 Over 2 EndFraction) squared


(x + StartFraction 5 Over 2 EndFraction) squared = StartFraction 33 Over 4 EndFraction


Which are solutions of x2 + 5x = 2?

User Moabi
by
2.9k points

2 Answers

14 votes
14 votes

Answer: d and e

Explanation:

edge 2021 :)

User Abhshkdz
by
3.0k points
19 votes
19 votes

Given:

The equation is:


x^2+5x=2

To find:

The solution of the given equation by completing the square.

Solution:

We have,


x^2+5x=2

We need to add the square of half of the coefficient of x on both sides.

Adding
\left((5)/(2)\right)^2 on both sides, we get


x^2+5x+\left((5)/(2)\right)^2=2+\left((5)/(2)\right)^2


\left(x+(5)/(2)\right)^2=2+(25)/(4)


\left(x+(5)/(2)\right)^2=(8+25)/(4)


\left(x+(5)/(2)\right)^2=(33)/(4)

Taking square root on both sides, we get


x+(5)/(2)=\pm \sqrt{(33)/(4)}


x=\pm (√(33))/(2)-(5)/(2)


x=(\pm √(33)-5)/(2)


x=(√(33)-5)/(2) and
x=(-√(33)-5)/(2)

Therefore, the solutions of the given equation are
x=(√(33)-5)/(2) and
x=(-√(33)-5)/(2).

User Des
by
2.7k points