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3 years ago

If x=3 is a solution of the equation 2x²-5x+k=0 find the value of k

Mathematics

2 answers:

Novosadov [1.4K]3 years ago

8 0

Answer:

k = - 3

Step-by-step explanation:

Given that x = 3 is a solution then it satisfies the equation, that is

2(3)² - 5(3) + k = 0

2(9) - 15 + k = 0

18 - 15 + k = 0

3 + k = 0 ( subtract 3 from both sides )

k = - 3

ipn [44]3 years ago

5 0

Answer: k = -3

Step-by-step explanation:

2x²-5x+k=0

Substitute x=3

2(3)^2-5(3)+k=0

2(9)-15+k=0

18-15+k=0

3+k=0

k=-3

To check if your answer is correct you can substitute x=3 and k = -3

2(3)^2-5(3)-3=0

2(9)-15-3=0

18-15-3=0

3-3=0

So k = -3 is correct

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Step-by-step explanation:

We are given that the students receive different versions of the math namely A, B, C and D.

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Then the probability that at-least 3 out of 5 students receive version A is given by,

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= $(\frac{1}{4})^3\times (\frac{3}{4})[\frac{3}{4}+\frac{1}{4}+(\frac{1}{4})^2]$

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3 years ago

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Answer:

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3 years ago

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Answer:

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R= {(x, y) ∈ A ✕ B| x R y ⇔ |x| = |y|}

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4 years ago

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4 years ago

Read 2 more answers

If x=3 is a solution of the equation 2x²-5x+k=0 find the value of k​

If x=3 is a solution of the equation 2x²-5x+k=0 find the value of k