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In the following question two equations ...

In the following question two equations are given in variables x and y. you have to solve these equations and determine the relation between x and y.
I. `2x^(2) + 15x + 28 =0`
II. `2y^(2) + 19 y + 45 = 0`

A

`y gt x`

B

`x gt y`

C

`x le y`

D

`x ge y`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given equations and determine the relationship between \( x \) and \( y \), we will follow these steps: ### Step 1: Solve the first equation for \( x \) The first equation is: \[ 2x^2 + 15x + 28 = 0 \] To solve this quadratic equation, we can use the factorization method. We need to find two numbers that multiply to \( 2 \times 28 = 56 \) and add up to \( 15 \). The numbers that satisfy this condition are \( 8 \) and \( 7 \). We can rewrite the equation as: \[ 2x^2 + 8x + 7x + 28 = 0 \] Now, we can group the terms: \[ (2x^2 + 8x) + (7x + 28) = 0 \] Factoring out the common terms: \[ 2x(x + 4) + 7(x + 4) = 0 \] Now, factor out \( (x + 4) \): \[ (2x + 7)(x + 4) = 0 \] Setting each factor to zero gives us: 1. \( 2x + 7 = 0 \) → \( x = -\frac{7}{2} = -3.5 \) 2. \( x + 4 = 0 \) → \( x = -4 \) So, the values of \( x \) are \( -3.5 \) and \( -4 \). ### Step 2: Solve the second equation for \( y \) The second equation is: \[ 2y^2 + 19y + 45 = 0 \] Again, we will use the factorization method. We need to find two numbers that multiply to \( 2 \times 45 = 90 \) and add up to \( 19 \). The numbers that satisfy this condition are \( 9 \) and \( 10 \). We can rewrite the equation as: \[ 2y^2 + 9y + 10y + 45 = 0 \] Now, we can group the terms: \[ (2y^2 + 9y) + (10y + 45) = 0 \] Factoring out the common terms: \[ y(2y + 9) + 5(2y + 9) = 0 \] Now, factor out \( (2y + 9) \): \[ (2y + 9)(y + 5) = 0 \] Setting each factor to zero gives us: 1. \( 2y + 9 = 0 \) → \( y = -\frac{9}{2} = -4.5 \) 2. \( y + 5 = 0 \) → \( y = -5 \) So, the values of \( y \) are \( -4.5 \) and \( -5 \). ### Step 3: Determine the relationship between \( x \) and \( y \) Now we have the following values: - For \( x \): \( -3.5 \) and \( -4 \) - For \( y \): \( -4.5 \) and \( -5 \) Now, we can compare the values: - \( -3.5 > -4.5 \) - \( -3.5 > -5 \) - \( -4 > -4.5 \) - \( -4 > -5 \) From the comparisons, we can conclude that: - In both cases, \( x \) is greater than \( y \). ### Final Conclusion Thus, the relationship between \( x \) and \( y \) is: \[ x > y \]
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