The original equation was

1.7e-3 = (0.0015 -x)^2 / (0.025 +1/2x)(0.025 + 1/2x)

Square root of both sides is
0.0412 = (0.0015-x) / (0.025 + 1/2x)

Solve for x and when I put in -0.001 or 1.0e-3 it says that it is incorrect, I don't know why??

please check

http://www.jiskha.com/display.cgi?id=1332100057

thank you I was looking for that post but couldn't find it.

You can find your previous posts by clicking on your name on a post.

ok thank you!!!

To solve for x in the equation 0.0412 = (0.0015 - x) / (0.025 + 1/2x), we can follow these steps:

1. Multiply both sides of the equation by (0.025 + 1/2x) to eliminate the fraction:
0.0412 * (0.025 + 1/2x) = 0.0015 - x

2. Distribute the 0.0412 to both terms on the left side:
0.00103 + 0.0206/x + 0.0206 = 0.0015 - x

3. Combine like terms:
0.0206/x + 0.02163 = 0.0015 - x

4. Move the terms involving x to one side of the equation:
0.0206/x + x = 0.0015 - 0.02163

5. Combine the constants on the right side:
0.0206/x + x = -0.02013

6. Multiply both sides by x to eliminate the fraction:
0.0206 + x^2 = -0.02013x

7. Rearrange the equation to a quadratic form:
x^2 + 0.02013x + 0.0206 = 0

Now we can solve the quadratic equation using various methods. For simplicity, we can use the quadratic formula:

x = (-b ± √(b^2 - 4ac)) / (2a)

In this case, a = 1, b = 0.02013, and c = 0.0206. Substituting these values into the formula:

x = [-(0.02013) ± √((0.02013)^2 - 4(1)(0.0206))] / (2(1))

Simplifying further:

x = [-0.02013 ± √(0.0004051269 - 0.0824)] / 2

x = [-0.02013 ± √(-0.0819948731)] / 2

Since the discriminant (the term inside the square root) is negative, it means that the equation has no real solutions. Therefore, the equation does not have any valid values for x.

That's why when you put in -0.001 or 1.0e-3, it is showing as incorrect because they are not valid solutions to the equation.