Math
posted by Untamed .
Solve the following quadratic equation(as exact values) using the quadratic formula.
x^210x15=0
I got 5+2sqrt10/2.
^ Sorry hard to write it out. But basically there is a 5 there, the negative sign is supposed to be under the positive sign, then there is a two outside of the radicand, and inside the radicand is 10, all under 2.

The answer is correct if it was meant to be, after cancelling the two's:
5±√(10) 
The answer is correct if it was meant to be (without the 2 in the denominator):
5±2√(10) 
Where does that two in the denominator go? Since it has to cancel out with all terms.

x=(b±sqrt(b²4ac))/2a
a=1
b=10
c=15
so substituting,
x=(10±sqrt((10)²4(1)(15)))/2
=(10±sqrt(160))/2
=(10±4sqrt(10))/2
=5±2sqrt(10)
You may have (like I did) subtracted 4ac (and got 40) instead of adding to get 160.
Respond to this Question
Similar Questions

Math ,help
how can i simplify this more its for the following problem: Problem #22 solve by using the quadratic formual. 5x^24x+1=0 this is where i am but i do not know how to go further. x = (4 (+/) sqrt (4))/(10) Problem #23 Solve by completing … 
Math
Use the quadratic formula to solve each of the following quadratic equations... 1. 2x^25x=3 2. 3x^22x+1=0 Rearrange the equation in quadratic formula form. 2x^2 5x 3 = 0 Then use the formula. Tell me what you don't understand about … 
help with solving
x^2+(x2)^2 = (2x6)^2 solve for x. thanks so much. Please keep in mind that tutors here won't simply do your work for you . I'm sure you'll get a better response if you show your work as far as you can get , so tutors will know where … 
Math
How do you graph the quadratic formula x^210x=11? 
algebra II
I'm quite clueless as to how to solve this. I know the quadratic equation but am not sure how to get this equation into the format to plug in to the quadratic... Solve the quadratic equation using the formula [1/(1+x)][1/(3x)]=(6/35) … 
math
15t^2+7t=2 The quadratic formula tells you that the solutions are: t = [b +/sqrt (b^2  4ac]/ (2a) In this case, a = 15, b = 7 and c = 2 solve the equation for t. What values for t will you get when you substitute the values you … 
quadratic equations
can you solve the equation using the quadratic formula x2 + 3x = 7? 
math
(4.35E2  x)(7.56E2 x ) ============================ (0.324 + 2x)2 Rearrange to get an expression of the form ax2 + bx + c = 0 and use the quadratic formula (solve for x. This gives: x = 1.05E2, 0.143 basically i understand they … 
Math
Solve the given quadratic equation exactly using the quadratic formula. Write the solutions in its simplest form. Using a calculator, determine all irrational solutions to the nearest thousandth. Separate the solutions with a comma … 
Math
Solve the given quadratic equation exactly using the quadratic formula. Write the solutions in its simplest form. Using a calculator, determine all irrational solutions to the nearest thousandth. Separate the solutions with a comma …