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Find the roots of the equations. Q. 6x...

Find the roots of the equations.
Q. `6x^(2)+7x-20=0`.

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To find the roots of the quadratic equation \(6x^2 + 7x - 20 = 0\), we can use the method of splitting the middle term. Here’s a step-by-step solution: ### Step 1: Write down the equation The given equation is: \[ 6x^2 + 7x - 20 = 0 \] ### Step 2: Identify \(a\), \(b\), and \(c\) In the quadratic equation \(ax^2 + bx + c = 0\), we have: - \(a = 6\) - \(b = 7\) - \(c = -20\) ### Step 3: Multiply \(a\) and \(c\) Calculate \(ac\): \[ ac = 6 \times (-20) = -120 \] ### Step 4: Find two numbers that multiply to \(ac\) and add to \(b\) We need two numbers that multiply to \(-120\) and add to \(7\). The numbers are \(15\) and \(-8\) because: \[ 15 \times (-8) = -120 \quad \text{and} \quad 15 + (-8) = 7 \] ### Step 5: Rewrite the middle term Now, rewrite the equation by splitting the middle term: \[ 6x^2 + 15x - 8x - 20 = 0 \] ### Step 6: Group the terms Group the terms: \[ (6x^2 + 15x) + (-8x - 20) = 0 \] ### Step 7: Factor by grouping Factor out the common terms in each group: \[ 3x(2x + 5) - 4(2x + 5) = 0 \] ### Step 8: Factor out the common binomial Now, factor out the common binomial \((2x + 5)\): \[ (2x + 5)(3x - 4) = 0 \] ### Step 9: Set each factor to zero Now, set each factor equal to zero: 1. \(2x + 5 = 0\) 2. \(3x - 4 = 0\) ### Step 10: Solve for \(x\) Solving the first equation: \[ 2x + 5 = 0 \implies 2x = -5 \implies x = -\frac{5}{2} \] Solving the second equation: \[ 3x - 4 = 0 \implies 3x = 4 \implies x = \frac{4}{3} \] ### Step 11: State the roots The roots of the equation \(6x^2 + 7x - 20 = 0\) are: \[ x = -\frac{5}{2} \quad \text{and} \quad x = \frac{4}{3} \] ---
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