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In each of these questions two equations...

In each of these questions two equations numbered I and II are given. You have to solve both the equations and give answer
I `8x^2+31x+21=0`
II `5y^2+11y-36=0`

A

if `xgey`

B

if `xgty`

C

if `xgey`

D

if x=y or the relationship can’t be established.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given equations step by step, we will follow these procedures: ### Step 1: Solve the first equation \(8x^2 + 31x + 21 = 0\) 1. **Identify coefficients**: Here, \(a = 8\), \(b = 31\), and \(c = 21\). 2. **Calculate the product \(ac\)**: \[ ac = 8 \times 21 = 168 \] 3. **Find two numbers that multiply to \(ac\) (168) and add to \(b\) (31)**: The numbers are \(24\) and \(7\) because \(24 \times 7 = 168\) and \(24 + 7 = 31\). 4. **Rewrite the equation using these numbers**: \[ 8x^2 + 24x + 7x + 21 = 0 \] 5. **Factor by grouping**: \[ (8x^2 + 24x) + (7x + 21) = 0 \] \[ 8x(x + 3) + 7(x + 3) = 0 \] \[ (8x + 7)(x + 3) = 0 \] 6. **Set each factor to zero**: \[ 8x + 7 = 0 \quad \Rightarrow \quad x = -\frac{7}{8} \] \[ x + 3 = 0 \quad \Rightarrow \quad x = -3 \] ### Step 2: Solve the second equation \(5y^2 + 11y - 36 = 0\) 1. **Identify coefficients**: Here, \(a = 5\), \(b = 11\), and \(c = -36\). 2. **Calculate the product \(ac\)**: \[ ac = 5 \times -36 = -180 \] 3. **Find two numbers that multiply to \(ac\) (-180) and add to \(b\) (11)**: The numbers are \(20\) and \(-9\) because \(20 \times -9 = -180\) and \(20 - 9 = 11\). 4. **Rewrite the equation using these numbers**: \[ 5y^2 + 20y - 9y - 36 = 0 \] 5. **Factor by grouping**: \[ (5y^2 + 20y) + (-9y - 36) = 0 \] \[ 5y(y + 4) - 9(y + 4) = 0 \] \[ (5y - 9)(y + 4) = 0 \] 6. **Set each factor to zero**: \[ 5y - 9 = 0 \quad \Rightarrow \quad y = \frac{9}{5} = 1.8 \] \[ y + 4 = 0 \quad \Rightarrow \quad y = -4 \] ### Step 3: Compare the values of \(x\) and \(y\) - From the first equation, we have two values for \(x\): - \(x_1 = -3\) - \(x_2 = -\frac{7}{8}\) - From the second equation, we have two values for \(y\): - \(y_1 = 1.8\) - \(y_2 = -4\) ### Step 4: Establish relationships 1. **Comparing \(x_1 = -3\) and \(y_2 = -4\)**: - Here, \(-3 > -4\) → \(x_1 > y_2\) 2. **Comparing \(x_1 = -3\) and \(y_1 = 1.8\)**: - Here, \(-3 < 1.8\) → \(x_1 < y_1\) 3. **Comparing \(x_2 = -\frac{7}{8}\) and \(y_2 = -4\)**: - Here, \(-\frac{7}{8} > -4\) → \(x_2 > y_2\) 4. **Comparing \(x_2 = -\frac{7}{8}\) and \(y_1 = 1.8\)**: - Here, \(-\frac{7}{8} < 1.8\) → \(x_2 < y_1\) ### Conclusion - The relationships established are: - \(x_1 > y_2\) and \(x_1 < y_1\) - \(x_2 > y_2\) and \(x_2 < y_1\) Since we have both cases where \(x\) is greater than \(y\) and \(x\) is less than \(y\), we conclude that the relationship between \(x\) and \(y\) cannot be established. ### Final Answer The answer is: **Relationship cannot be established.**
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