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Solve the equations given below and give...

Solve the equations given below and give answer
1) if `x lt y` 2) if `x gt y`
3) if `c ge y` 4) if `x le y`
5) if x=y or no relation can be established
I. `2x^2-15=7x` II. `17y=-7-6y^2`

A

if `x lt y`

B

if `x gt y`

C

if `x ge y`

D

if x=y or no relation can be established

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equations given in the question, we will follow these steps: ### Step 1: Solve the first equation \(2x^2 - 15 = 7x\) 1. Rearrange the equation: \[ 2x^2 - 7x - 15 = 0 \] 2. Factor the quadratic: - We need two numbers that multiply to \(2 \times -15 = -30\) and add to \(-7\). - The numbers are \(-10\) and \(3\). - Rewrite the equation: \[ 2x^2 - 10x + 3x - 15 = 0 \] 3. Group the terms: \[ (2x^2 - 10x) + (3x - 15) = 0 \] \[ 2x(x - 5) + 3(x - 5) = 0 \] 4. Factor out the common term: \[ (2x + 3)(x - 5) = 0 \] 5. Set each factor to zero: \[ 2x + 3 = 0 \quad \text{or} \quad x - 5 = 0 \] \[ x = -\frac{3}{2} \quad \text{or} \quad x = 5 \] ### Step 2: Solve the second equation \(17y = -7 - 6y^2\) 1. Rearrange the equation: \[ 6y^2 + 17y + 7 = 0 \] 2. Factor the quadratic: - We need two numbers that multiply to \(6 \times 7 = 42\) and add to \(17\). - The numbers are \(14\) and \(3\). - Rewrite the equation: \[ 6y^2 + 14y + 3y + 7 = 0 \] 3. Group the terms: \[ (6y^2 + 14y) + (3y + 7) = 0 \] \[ 2y(3y + 7) + 1(3y + 7) = 0 \] 4. Factor out the common term: \[ (3y + 7)(2y + 1) = 0 \] 5. Set each factor to zero: \[ 3y + 7 = 0 \quad \text{or} \quad 2y + 1 = 0 \] \[ y = -\frac{7}{3} \quad \text{or} \quad y = -\frac{1}{2} \] ### Step 3: Compare the values of \(x\) and \(y\) 1. Values of \(x\): - \(x_1 = 5\) - \(x_2 = -\frac{3}{2} = -1.5\) 2. Values of \(y\): - \(y_1 = -\frac{7}{3} \approx -2.33\) - \(y_2 = -\frac{1}{2} = -0.5\) ### Step 4: Analyze the relationships 1. **If \(x < y\)**: - For \(x = 5\) and \(y = -\frac{7}{3}\), \(5 > -\frac{7}{3}\). - For \(x = 5\) and \(y = -\frac{1}{2}\), \(5 > -\frac{1}{2}\). - For \(x = -1.5\) and \(y = -\frac{7}{3}\), \(-1.5 > -\frac{7}{3}\). - For \(x = -1.5\) and \(y = -\frac{1}{2}\), \(-1.5 < -0.5\). 2. **If \(x > y\)**: - For \(x = 5\), \(x\) is always greater than both \(y\) values. - For \(x = -1.5\) and \(y = -\frac{7}{3}\), \(-1.5 > -2.33\). - For \(x = -1.5\) and \(y = -\frac{1}{2}\), \(-1.5 < -0.5\). 3. **If \(c \geq y\)**: - This depends on the value of \(c\) which is not provided. 4. **If \(x \leq y\)**: - This is true for \(x = -1.5\) and \(y = -\frac{1}{2}\). 5. **If \(x = y\) or no relation can be established**: - No values of \(x\) and \(y\) are equal. ### Conclusion From the analysis, we can conclude: - \(x\) can be greater than \(y\) in most cases. - The only case where \(x\) is less than \(y\) is when \(x = -1.5\) and \(y = -\frac{1}{2}\).
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