SOLUTION: square root of 5 more than twice a number is 7

Question 994111: square root of 5 more than twice a number is 7
Found 2 solutions by Theo, MathTherapy:
Answer by Theo(13342) (Show Source): You can put this solution on YOUR website!
7 = 2x + sqrt(5)

subtract 2x from both sides of the equation to get:

7 - 2x = sqrt(5)

square both sides of the equation to get:

(7-2x)^2 = 5

simplify the left side of the equation by squaring it to get:

49 - 28x + 4x^2 = 5

subtract 5 from both sides of the equation to get:

49 - 5 - 28x + 4x^2 = 0

combine like terms to get:

44 - 28x + 4x^2 = 0

rearrange the terms in descending order to get:

4x^2 - 28x + 44 = 0

factor out the gcf to get:

4 * (x^2 - 7x + 11) = 0

divide both sides of the equation by 4 to get:

x^2 - 7x + 11 = 0

factor the quadratic using the quadratic formula to get:

x = 4.618 and x = 2.382

answers are rounded to the third decimal place.

here's some info on the quadratic formula.

http://www.regentsprep.org/regents/math/algtrig/ate3/quadformula.htm

Answer by MathTherapy(10555) (Show Source): You can put this solution on YOUR website!

square root of 5 more than twice a number is 7

Number:
RELATED QUESTIONS
The square root of 5 more than twice a number is 7. Find the... (answered by Construe)
The square root of 5 more than twice a number is 7. Find the... (answered by fcabanski,MathTherapy)
if 3 more than twice the square root of a number is 17, find the... (answered by mananth)
Write an equation and solve Five more than twice the square root of a number is 17.... (answered by ikleyn)
one-fourth of a number yields ten less than two times a number five more than a square (answered by solver91311)
If eighteen more than the square root of a number is 307 what's the... (answered by rfer)
Twice the square of a number is 10 more than the number. What is the... (answered by mananth)
the square of a number is 195 more than twice the number. find the number (answered by Cromlix)
Find the number that is 3 more than twice the square... (answered by fcabanski)