SOLUTION: Describe the values of b in the following equations, that will give one or more real number soulutions. (a) 3x^2+bx-3=0 (b) 5x^2+bx+1=0 (c) -3x^2+bx-3=0 (d) Write a rule for

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Question 93585: Describe the values of b in the following equations, that will give one or more real number soulutions.
(a) 3x^2+bx-3=0
(b) 5x^2+bx+1=0
(c) -3x^2+bx-3=0
(d) Write a rule for judging if an equation has solutions by looking at it in standard form.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
Describe the values of b in the following equations, that will give one or more real number soulutions.
(a) 3x^2+bx-3=0
b^2-4ac>=0
b^2>=4ac
b^2>=4*3*-9
b^2>=-108
True for every value of b
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(b) 5x^2+bx+1=0
b^2>=4ac
b^2>=4*5*1
b^2>=20
b>=2sqr5 or b<=-2sqrt5
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(c) -3x^2+bx-3=0
b^2>=4ac
b^2>=5*-3*3
b^2>=-45
True for ever value of b
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(d) Write a rule for judging if an equation has solutions by looking at it in standard form.
b^2 must be >= 4ac
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Cheers,
Stan H.