Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
another math question.... i've attempted it but im horrible.?
the product of two consecutive positive intergers is 11 more than their sum. Find the intergers.
Thanks guys-
Evey
21 Answers
- Jun AgrudaLv 71 decade agoFavorite Answer
1st integer—x:
x(x + 1) = x + x + 1 + 11
x² + x = 2x + 12
x² - 1/2x = 12 + (- 1/2)²
x² - 1/2x = 48/4 + 1/4
(x - 1/2)² = 49/4
x - 1/2 = 7/2
x = 8/2 or 4
2nd integer:
= 4 + 1
= 5
Answer: 4 and 5 are the integers.
- ?Lv 71 decade ago
Let x be the first positive integer
then x+1 is the second
x(x+1)= x +(x+1) + 11, the right side is the product of consecutive positive integers, the left side is the sum of the positive integers plus 11
x^2 + x = 2x + 12
x^2 -x - 12 = 0
factor
(x-4)(x+3) = 0
x - 4 = 0 so x = 4
x + 3 = 0 so x would be -3 but you are dealing with positive integers so -3 is not an answer
the integers are 4, and 5 the product is 20 and the sum is 9 and the product is indeed 11 more than the sum
- Anonymous1 decade ago
let me break it down for you
the product -- this means we're talking about multiplying numbers together
of two -- well that makes it easy, there's only two numbers to multiply
consecutive -- the numbers are in order as according to...
positive integers -- yes, it's spelled i-n-t-e-g-e-r-s, no R in the middle. positive means the numbers are greater than zero, integers are whole numbers. so "two consecutive positive integers" means a positive integer and the very next one in counting order. for example, 1 and 2, or maybe 2 and 3, or perhaps 3 and 4. well, we shall find out. note that if we subtract the first number from the second number we always get 1. so if we let x represent the smaller number, then we can represent the next consecutive integer after x as x+1.
alright, I think we can start taking bigger steps
the product...is 11 more than their sum
well the product of x and x+1 is simply x(x+1)
their sum means we add them together: x + x+1, which simplifies to 2x+1
if the product is more (11 more in fact) than the sum, that means it is a bigger number. so if we start with their sum, how do we make that a bigger number, specifically a bigger number that is 11 more? seems painfully obvious, doesn't it? we just add 11 to that sum. so now we have an equation.
product = sum + 11, which is
x(x+1) = 2x + 1 + 11
let's perform the multiplication indicated on the left, and simplify the right
x^2 + x = 2x + 12
now subtract what's on the right from both sides
x^2 - x -12 = 0
I think we can factor
(x - 4)(x + 3) = 0
if two numbers multiplied together equal zero, then one of them must be zero
so if x-4=0, then x=4
and if x+3=0, then x=-3
hence we have two possible solutions: x=4, x=-3
but the problem said we were looking for positive integers.
therefore x=4 is what we want. now remember x was the first integer. what was the second one? none other than x+1, which in this case is 4+1=5.
now we are finally done. 4 and 5 are the numbers we sought.
- 1 decade ago
Let x be the first integer
x + 1 will be the second integer
(x)(x+1) = x+x+1+11 (add 11 to this side because the product is 11 more, so to make this an equation we must make both sides equal)
x^2+x = 2x+12
x^2-x-12 = 0 (now we must factor)
(x-4)(x+3) = 0
x = -3, 4
Now we go back to our original equation x values and plug -3 and 4 in for them.
For x = -3
First Integer = -3
Second Integer = (-3) + 1 = -2
We know -3 and -2 work because there product (6) is 11 more than their sum (-5).
For x = 4
First Integer = 4
Second Integer = (4) + 1 = 5
We know 4 and 5 work because there product (20) is 11 more than their sum (9).
So you have two sets of integers (-3 and -2) and (4 and 5).
- How do you think about the answers? You can sign in to vote the answer.
- OliverLv 41 decade ago
Let the first integer = x. Then the other integer is x + 1...
(x)(x + 1) = x + (x + 1) + 11
x^2 + x = 2x + 12
x^2 - x - 12 = 0
(x - 4)(x + 3) = 0
Therefore, x = 4 or -3. As we are told the integers are positive, just take x = 4. Therefore, x + 1 = 4 + 1 = 5.
The two consecutive integers are 4 and 5.
- Anonymous1 decade ago
4 and 5
- Anonymous1 decade ago
4 and 5
- nyc_kidLv 71 decade ago
Let the 2 consecutive positive integers be n , n+1:
n(n+1) = 11 + n + (n+1) = 12 + 2n
n^2 -n -12 = 0
(n-4)(n+3) = 0
n = 4, n = -3 .
n = -3 is dropped since we require positive integers.
So, the answer is 4 and 5
- Anonymous1 decade ago
Product- The answer to a multiplication problem.
Consecutive - In a row.
Positive - 1,2,3,4,5......
Integers- a set of whole numbers and there opposites. -3,-2,-1,0,1,2,3.
Sum- Answer ot an addition problem
lets start at the beginning
1 x 2 = 3
1 + 2= 3...
So its not 1 & 2.
2&3.
2 x 3 = 6
2 +3 = 5
nope.
3 & 4.
3 x 4 = 12
3 + 4 = 7
nope.
4 & 5.
4 x 5 = 20
4 + 5 = 9
20 -9 = 11
Yes!
So ur answer is 4 & 5
4 x 5 = 20
then 5 + 4 = 9
20 - 9 = 11
:D
-xoxo
- ?Lv 41 decade ago
Let x be the first number so x +1 is the number after it
x(x + 1) = x + (x + 1) + 11
x^2 + x = 2x +12
x^2 + x - 2x - 12 = 0
x^2 - x - 12 = 0
(x - 4)(x + 3) = 0
x = 4, -3
Since it can only be a positive number it is 4 and 5