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

User Gilean
by
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2 Answers

0 votes

Answer: k = -3

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

User Ottomeister
by
4.6k points
5 votes

Answer:

k = - 3

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

User Mirdrack
by
5.6k points