SOLUTION: please help me solve this equation 2. The sum of two numbers is 23 and their product is 120. find the two numbers

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Question 1174930: please help me solve this equation
2. The sum of two numbers is 23 and their product is 120. find the two numbers
Found 2 solutions by greenestamps, ewatrrr:
Answer by greenestamps(13200) (Show Source):
You can put this solution on YOUR website!

Informally first....

Look at pairs of numbers with a sum of 23 and find a pair with a product of 120.

You can shorten the search by noting that, with a product of 120, one of the numbers must be a multiple of 5. So the numbers are either 5 and 18 or 15 and 8.

5*18 = 90; 15*8 = 120. So the two numbers are 15 and 8.

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Now using formal algebra....

let x be one of the two numbers
then 23-x is the other (because their sum is 23)

The product of the two numbers is 120:

To solve this algebraically, you need to factor the quadratic expression by finding two numbers whose sum is 23 and whose product is 120.

But that's what you had to do with the original problem!

So the formal algebraic approach doesn't get you any closer to the solution of the problem.

However, you should understand the process for solving the problem algebraically.

or

Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website!

Hi x + y = 23 xy = 120 0r y =120/x x + 120/x = 23 x^2 + 120 = 23x x^2 - 23x + 120 = 0 (x-15)(x-8) = 0 0r use x = 15 0r x = 8 Wish You the Best in your Studies.