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Each root of the equation ax^2 + bx + c ...

Each root of the equation `ax^2 + bx + c = 0` is decreased by 1. The quadratic equation with these roots is `x^2 + 4x + 1 = 0`. The numerical value of b + c is……………….

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To solve the problem, we will start by analyzing the given information and using the properties of roots of quadratic equations. ### Step 1: Understand the given equations We are given that each root of the equation \( ax^2 + bx + c = 0 \) is decreased by 1, resulting in the roots of the new equation \( x^2 + 4x + 1 = 0 \). ### Step 2: Identify the roots of the new equation The roots of the equation \( x^2 + 4x + 1 = 0 \) can be found using the sum and product of roots: - The sum of the roots \( \alpha + \beta = -\text{coefficient of } x = -4 \) - The product of the roots \( \alpha \beta = \text{constant term} = 1 \) ### Step 3: Relate the roots of the original equation If the roots of the original equation \( ax^2 + bx + c = 0 \) are \( \alpha \) and \( \beta \), then the roots of the new equation are \( \alpha - 1 \) and \( \beta - 1 \). Therefore, we can express the sum and product of the new roots: - Sum of the new roots: \[ (\alpha - 1) + (\beta - 1) = \alpha + \beta - 2 = -4 - 2 = -6 \] - Product of the new roots: \[ (\alpha - 1)(\beta - 1) = \alpha \beta - (\alpha + \beta) + 1 = 1 - (-4) + 1 = 1 + 4 + 1 = 6 \] ### Step 4: Set up the equations for the original roots From the properties of the original equation \( ax^2 + bx + c = 0 \): - The sum of the roots \( \alpha + \beta = -\frac{b}{a} \) - The product of the roots \( \alpha \beta = \frac{c}{a} \) ### Step 5: Set up the equations based on the new roots From the new roots, we have: 1. \(-\frac{b}{a} - 2 = -6\) (from the sum of the new roots) 2. \(\frac{c}{a} = 6\) (from the product of the new roots) ### Step 6: Solve for \( b \) and \( c \) From the first equation: \[ -\frac{b}{a} - 2 = -6 \implies -\frac{b}{a} = -4 \implies \frac{b}{a} = 4 \implies b = 4a \] From the second equation: \[ \frac{c}{a} = 6 \implies c = 6a \] ### Step 7: Find \( b + c \) Now we can find \( b + c \): \[ b + c = 4a + 6a = 10a \] ### Step 8: Determine the numerical value of \( b + c \) Since \( a \) is a non-zero constant, the numerical value of \( b + c \) can be expressed as: \[ b + c = 10a \] However, we need the numerical value, and since \( a \) can be any non-zero value, we can set \( a = 1 \) for simplicity: \[ b + c = 10 \cdot 1 = 10 \] Thus, the numerical value of \( b + c \) is **10**.
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