To find the answer to "What two numbers have a product of 5 and a sum of 28?" we first state what we know. We are looking for x and y and we know that x • y = 5 and x + y = 28.
Before we keep going, it is important to know that x • y is the same as y • x and x + y is the same as y + x. The two variables are interchangeable. Which means that when we create one equation to solve the problem, we will have two answers.
To solve the problem, we take x + y = 28 and solve it for y to get y = 28 - x. Then, we replace y in x • y = 5 with 28 - x to get this:
x • (28 - x) = 5
Like we said above, the x and y are interchangeable, therefore the x in the equation above could also be y. The bottom line is that when we solved the equation we got two answers which are the two numbers that have a product of 5 and a sum of 28. The numbers are:
0.17973
27.82027
That's it! The two numbers that have a product of 5 and a sum of 28 are 0.17973 and 27.82027 as proven below:
0.17973 • 27.82027 ≈ 5
0.17973 + 27.82027 = 28
Note: Answers are rounded up to the nearest five decimals if necessary so the answers may not be exact.
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