To find the positive value for x, we need to solve the equation 2x^2 - 7x - 4 = 45 for x.
First, let's rearrange the equation to set it equal to zero:
2x^2 - 7x - 4 - 45 = 0
2x^2 - 7x - 49 = 0
Next, we can solve for x using the quadratic formula:
x = (-(-7) ± √((-7)^2 - 4*2*(-49)))/(2*2)
x = (7 ± √(49 + 392))/4
x = (7 ± √441)/4
x = (7 ± 21)/4
Therefore, x can be calculated as follows:
x1 = (7 + 21)/4 = 28/4 = 7
x2 = (7 - 21)/4 = -14/4 = -3.5
Since we are looking for the positive value for x, we choose the solution x = 7.
the area of a rectangle can be expressed by 2x^2-7x-4. if the rectangle has an area of 45, find the positive value for x
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