Question
The width of a yard is four less than a number. The length is five more than twice that same number. The area of the yard is 15 meters. Write and solve a quadratic equation to find the value of X; then choose the answer that best describes the value of X
Answers
Answered by
GPT 3.5
Let's denote the number as x.
According to the problem, the width of the yard is four less than the number x, which can be expressed as x - 4.
The length of the yard is five more than twice the number x, which can be expressed as 2x + 5.
The area of the yard is calculated by multiplying the width and the length, so we have the equation:
(x - 4)(2x + 5) = 15
Expanding the left side of the equation gives:
2x^2 + 5x - 8x - 20 = 15
Combine like terms:
2x^2 - 3x - 20 = 15
Rearrange the equation to standard quadratic form:
2x^2 - 3x - 35 = 0
Now we can solve this quadratic equation by factoring, completing the square, or using the quadratic formula. Let's use factoring:
(2x + 7)(x - 5) = 0
Setting each factor equal to zero:
2x + 7 = 0 or x - 5 = 0
Solving each equation:
2x = -7 or x = 5
Dividing by 2 in the first equation:
x = -7/2 or x = 5
Therefore, the possible values for x are -7/2 or 5. The answer that best describes the value of x is 5.
According to the problem, the width of the yard is four less than the number x, which can be expressed as x - 4.
The length of the yard is five more than twice the number x, which can be expressed as 2x + 5.
The area of the yard is calculated by multiplying the width and the length, so we have the equation:
(x - 4)(2x + 5) = 15
Expanding the left side of the equation gives:
2x^2 + 5x - 8x - 20 = 15
Combine like terms:
2x^2 - 3x - 20 = 15
Rearrange the equation to standard quadratic form:
2x^2 - 3x - 35 = 0
Now we can solve this quadratic equation by factoring, completing the square, or using the quadratic formula. Let's use factoring:
(2x + 7)(x - 5) = 0
Setting each factor equal to zero:
2x + 7 = 0 or x - 5 = 0
Solving each equation:
2x = -7 or x = 5
Dividing by 2 in the first equation:
x = -7/2 or x = 5
Therefore, the possible values for x are -7/2 or 5. The answer that best describes the value of x is 5.