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What is the value of k in the quadratic ...

What is the value of k in the quadratic polynomial `kx^(2) + 4x + 3k`, if the sum of the zeroes is equal to their product?

A

`-(4)/(3)`

B

`(2)/(3)`

C

`(1)/(0)`

D

`-5`

Text Solution

AI Generated Solution

The correct Answer is:
To find the value of \( k \) in the quadratic polynomial \( kx^2 + 4x + 3k \) such that the sum of the zeroes is equal to their product, we will follow these steps: ### Step 1: Identify the coefficients The given quadratic polynomial is in the form \( ax^2 + bx + c \), where: - \( a = k \) - \( b = 4 \) - \( c = 3k \) ### Step 2: Write the formulas for the sum and product of the roots For a quadratic polynomial \( ax^2 + bx + c \): - The sum of the roots (zeroes) is given by \( -\frac{b}{a} \). - The product of the roots is given by \( \frac{c}{a} \). ### Step 3: Calculate the sum and product of the roots Using the coefficients identified: - Sum of the roots \( S = -\frac{b}{a} = -\frac{4}{k} \) - Product of the roots \( P = \frac{c}{a} = \frac{3k}{k} = 3 \) ### Step 4: Set the sum equal to the product According to the problem, the sum of the zeroes is equal to their product: \[ -\frac{4}{k} = 3 \] ### Step 5: Solve for \( k \) To solve for \( k \), we first multiply both sides by \( k \) (assuming \( k \neq 0 \)): \[ -4 = 3k \] Now, divide both sides by 3: \[ k = -\frac{4}{3} \] ### Conclusion The value of \( k \) is: \[ \boxed{-\frac{4}{3}} \]
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