x²-2x-56 find the roots
Answers
Solving x2-2x-56 = 0 by the Quadratic Formula .
According to the Quadratic Formula, x , the solution for Ax2+Bx+C = 0 , where A, B and C are numbers, often called coefficients, is given by :
- B ± √ B2-4AC
x = ————————
2A
In our case, A = 1
B = -2
C = -56
Accordingly, B2 - 4AC =
4 - (-224) =
228
Applying the quadratic formula :
2 ± √ 228
x = —————
2
Can √ 228 be simplified ?
Yes! The prime factorization of 228 is
2•2•3•19
To be able to remove something from under the radical, there have to be 2 instances of it (because we are taking a square i.e. second root).
√ 228 = √ 2•2•3•19 =
± 2 • √ 57
√ 57 , rounded to 4 decimal digits, is 7.5498
So now we are looking at:
x = ( 2 ± 2 • 7.550 ) / 2
Two real solutions:
x =(2+√228)/2=1+√ 57 = 8.550
or:
x =(2-√228)/2=1-√ 57 = -6.550
Two solutions were found :
x =(2-√228)/2=1-√ 57 = -6.550
.
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hope it helps u
I got the answer
the. two roots are
1) 8.545
2) 6.545
Hope it will help you
