Carcass wrote:

If the sum of two numbers is 19 and their product is 88, what is the difference between the numbers?

A) 2

B) 3

C) 4

D) 5

E) 6

Another approach:

Let x = one of the numbers

Let y = the other number

The sum of two numbers is 19....We can write:

x + y = 19... and their product is 88xy = 88We have two equations:

x + y = 19xy = 88Rewrite

x + y = 19 as

y = 19 - xNow take

xy = 88 and replace

y with

19 - x to get:

(x)(19 - x) = 88Expand to get: 19x - x² = 88

Rearrange to get: x² - 19x + 88 = 0

Factor to get: (x - 11)(x - 8) = 0

So, EITHER x = 11 OR x = 8

If x = 11, then y = 8

If x = 8, then y = 11

What is the difference between the numbers?In either case, the difference = 11 - 8 = 3

Cheers,

Brent

Answer:

Cheers,

Brent

_________________

Brent Hanneson – Creator of greenlighttestprep.com

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