How do I use the following number to get the right result in this equation?

Question

In the following equation

x-32/3.142+110/3.142=28

x≈3.17505

x + 24.825 = 28

However we are given the equation in the test without telling us that the equation equals 28 so it would look like this:

x-32/3.142+110/3.142=

Using Wolf rama alpha, it gives me x + 24.825, by using a list of mathetical constants found in wikipedia (just type list of mathematical constants and you will see it.

and not a random number outside of that list how do I force the equation to give me 28? Which additional steps are necessary to add to this equation?

Answer 1

The 2 fractions on the right can be added because they have a common denominator. To do this, you MUST remember that the negative sign goes along with the 32. The results in:

or

Plug in into a calculator to get approx 24.825 so the results is: x + 24.825

At this point, you can plug any number you wish into the expression to result in any answer you want. The expression x + 24.825 is not uniquely equal to 28. It is ONLY equal to 28 for one single value of x, and that is x ≈ 3.17505. But if someone told you to make the expression equal to 28, you could find the value of x that would accomplish that. You would set the expression equal to 28:

x + 24.825 = 28 then subtract 24.825 from both sides to get:

x = 3.175 (you can use more decimal points to get any level of accuracy you want)

Answer 2

Hi Jeremy

If I'm reading this right, you'll be given an algebraic expression like , and also told that x≈3.17505. Does that sound right?

So let's simplify the expression. Those two fraction have a common denominator (which appears to be approximately π), so we can combine them by simply adding their numerators.

Now just substitute in the approximate value of x, and this becomes a problem for your calculator. The value of the entire expression is approximately 28.

Let me know if this needs more clarification or if I assumed wrong about the problem!