Solve by using the quadratic formula. x2 = 5x + 8?

Answer 1

First change the equation so it's in the correct format....x2-5x-8=0. in the quadratic formula a=1 b=-5 c=-8. then plug the numbers into the formula... x= -5 +/- √(-5)(-5)- 4(1)(-8) / 2(1)
then the top should equal 57/2
which equals 28.5
the answer is x= 5+/- 28.5.
Hope I did my math right and this helps!

Answer 2

Its an ugly number if you just try to factor so the quadratic formula is best more work but a better looking answer but first add 2 to both sides to set the equation equal to 0 the quadratic formula is (-b±√b^2-4ac)/2a ax^2+bx+c where in this case a=1 b=5 c=2 plug in the numbers and solve. (-5±√5^2-4(1)(2))/2(1) (-5±√25-8)/2 (-5±√17)/2 you can solve further but it's a weird number so you can just leave is as is. I hope this helps

Answer 3

x² = 5x + 8

Subtract the right side from both sides.

x² - 5x - 8 = 0

Solve using quadratic formula.

ax² + bx + c = 0
x = (-b ± √(b² - 4ac))/2a

x = (5 ± √(25 + 32))/2

x = (5 ± √(57))/2

or

x ≈ 6.275, x ≈ -1.275
.