x² + 5x - 3 = 0
x = [- 5 ± √(25 + 12)] / 2
x = [- 5 ± √37] / 2
x = 0.54, x = - 5.54 ( to 2 decimal places)
2007-08-16 02:05:39
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answer #1
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answered by Como 7
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Completing the square
x² + 5x = 3
x² + 5x +_____ = 3 +_____
x² + 5x + 25/4 = 3 + 25/4
(x + 5/2)(x + 5/2) = 12/4 + 25/4
(x + 5/2)² = 37/4
(âx + 5/2)² = ± â37 / â4
x + 5/2 = ± â37 / 2
x + 5/2 - 5/2 = - 5/2 ± â37/2
x = - 5/2 ± â37/2
x = - 5/2 ± 6.08276253 / 2
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Solving for +
x = - 5/2 + 6.08276253 / 2
x = 1.08276253 / 2
x = 0.541381265
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Solving for -
x = - 5/2 - 6.08276253 / 2
x = - 11.08276253 / 2
x = - 5.541381265
- - - - - - -s-
2007-08-12 03:07:01
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answer #2
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answered by SAMUEL D 7
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there is a formula for solving quadratic eq. which is called SHREEDHARACHARYA METHOD
let a general eq. a x^2 + bx + c = 0
then the roots will be, x1 = -b +( b^2 - 4 ac )^1/2 divided by 2a
and x2 = -b - ( b^2 - 4ac )^1/2 divided by 2a
here a= 1, b= 5, c= -3
x1 = -5 + ( 5^2- 4*1*-3 )^1/2 divided by 2*1
= -5 + ( 37)^1/2 / 2
= 0.5413
x2 = -5 - (37)^1/2 / 2
= - 5.54138
2007-08-12 02:52:21
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answer #3
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answered by pihoo 2
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x^2+5x-3 = 0
delta = b^2-4ac = 5^2+4*3 = 25+12 = 37
x1=[-5-sqrt(37)]/2
x2=[-5+sqrt(37)]/2
2007-08-12 02:41:57
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answer #4
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answered by Shadow 3
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you break the middle part having coefficient of x so that equation can be factorized(common parts come togeather). Here it cannot be done. So use discriminant method to find the D and x.
x= [-b+-sqrt(b^2-4ac)]/2a
so, x=[-5+-sqrt(25+12)]/2
solve it. this is the answer
2007-08-12 02:40:13
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answer #5
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answered by ʞzɹәႨnɹ 2
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