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3 years ago

Help me please!! This is timed and I’m stuck

Mathematics

2 answers:

marshall27 [118]3 years ago

5 0

Answer:

B. 13/2

Step-by-step explanation:

Given equation:

2x² + 7x - 15 = 0

It has roots r and s.

We know how to find the sum and product of roots.

Sum of roots:

r + s = -7/2

Product of roots:

rs = -15/2

Use the above two equations to work out the value of r - s:

$r - s = \sqrt{(r - s)^2} =$
$\sqrt{(r+s)^2-4rs} =$
$\sqrt{(-7/2)^2-4(-15/2)} =$
$\sqrt{169/4} =13/2$

Correct choice is B

Brums [2.3K]3 years ago

3 0

Answer:

D is the correct answer

Step-by-step explanation:

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Step-by-step explanation:

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horrorfan [7]

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Step-by-step explanation:

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Answer:

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3 years ago

Read 2 more answers