SOLUTION: Find three consecutive positive integers such that the product of the first and third, minus the second, is 1 more than 4 times the third.

Algebra.Com
Question 148935: Find three consecutive positive integers such that the product of the first and third, minus the second, is 1 more than 4 times the third.
Found 2 solutions by ankor@dixie-net.com, checkley77:
Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
Find three consecutive positive integers such that the product of the first and third, minus the second, is 1 more than 4 times the third.
:
Let the three consecutive numbers be x, (x+1), (x+2)
:
Write an equation for this statement:
"product of the first and third, minus the second,is 1 more than 4 times the third."
x(x+2) - (x+1) = 4(x+2) + 1
:
x^2 + 2x - x - 1 = 4x + 8 + 1
:
x^2 + x -1 = 4x + 9
:
Arrange as a quadratic equation on the left
x^2 + x - 4x - 1 - 9 = 0
:
x^2 - 3x - 10 = 0
Factors to:
(x-5)(x+2) = 0
Positive solution wanted
x = +5, 6, 7 are the 3 numbers
;
:
Check solution in the statement
"product of the first and third, minus the second,is 1 more than 4 times the third."
5*7 - 6 = 4(7) + 1
35 - 6 = 28 + 1

Answer by checkley77(12844)   (Show Source): You can put this solution on YOUR website!
LET X BE THE FIRST NTEGER, (X+1) BE THE SECOND & 9X+2) BE THE THIRD.
X(X+2)-(X+1)=4(X+2)+1
X^2+2X-X-1=4X+8+1
X^2+2X-X-4X-1-8-1=0
X^2-3X-10=0
(X-5)(X+2)=0
X-5=0
X=5 ANSWER FOR THE FIRST INTEGER.
5+1=6 THE SECOND.
5+2=7 THE THIRD.
PROOF:
5*7-6=4*7+1
35-6=28+1
29=29


RELATED QUESTIONS

Find three consecutive positive integers such that the product of the first and third,... (answered by ankor@dixie-net.com)
find 3 consecutive positive integers such that the product of the first and third, minus... (answered by sudhanshu_kmr)
find Three consecutive positive integers such that the of the first and third, minus the... (answered by stanbon)
Find three consecutive positive integers such that that product of the first and third,... (answered by swincher4391,hamsanash1981@gmail.com)
please help Find three consecutive positive integers such that the product of the... (answered by josgarithmetic)
Find three consecutive positive even integers such that the product of the second and... (answered by dabanfield)
Find three consecutive positive even integers such that the product of the second and... (answered by solver91311)
find three consecutive positive integers such that the product of the second and third... (answered by Greenfinch)
Find three consecutive positive even integers such that the product of the second and... (answered by JBarnum)