SOLUTION: {{{3x^2-4x-5=0}}} I'm supposed to use the quadratic formula to solve the following and leave the irrational roots in the simplest radical form.
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-> SOLUTION: {{{3x^2-4x-5=0}}} I'm supposed to use the quadratic formula to solve the following and leave the irrational roots in the simplest radical form.
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Question 19277: I'm supposed to use the quadratic formula to solve the following and leave the irrational roots in the simplest radical form. Answer by mmm4444bot(95) (Show Source):
You can put this solution on YOUR website! Hello There:
The quadratic formula solves equations in the form of:
a*x^2 + b*x + c = 0 when you're given the values of a, b, and c.
In your equation we have a = 3, b = -4, and c = -5.
The quadratic formula is:
x = [-b +/- sqrt(b^2 - 4*a*c)]/[2*a]
Substitute the given values for a, b, and c.
x = [-(-4) +/- sqrt(4^2 - 4*3)]/[2*3]
x = [4 +/- sqrt(16 + 60)]/6
x = [4 +/- sqrt(76)]/6
Since 76 = 2*2*19, the square root of 76 simplifies to 2*sqrt(19)
x = [4 +/- 2*sqrt(19)]/6
There are two solutions.
x = 4/6 + 2*sqrt(19)/6 and x = 4/6 - 2*sqrt(19)/6
x = 2/3 + sqrt(19)/3
x = 2/3 - sqrt(19)/3
~ Mark