SOLUTION: Find 2 consecutive 2-digit numbers whose product is 812.

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Question 414694: Find 2 consecutive 2-digit numbers whose product is 812.
Found 3 solutions by ewatrrr, emargo19, Alan3354:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

2 consecutive 2-digit numbers

Let x and (x+1) represent the numbers

Question states***

  x(x+1) = 812

Solving for x

 x^2 + x - 812 = 0

factoring

(x+29)(x-28)= 0

(x+29)= 0  x = -29     The 2 consecutive 2-digit numbers are -29,-28

(x-28)= 0  x = 28      The 2 consecutive 2-digit numbers are 28,29

Answer by emargo19(101) About Me  (Show Source):
You can put this solution on YOUR website!
Let 1st number=x
2nd number=x+1
x%28x%2B1%29=812
x%5E2%2Bx=812
x%5E2%2Bx-812=0
Lets use the quadratic equation to factor the equation
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1 b=1 c=-812
x+=+%281+%2B-+sqrt%28+1%5E2-4%2A1%2A-812+%29%29%2F%282%2A1%29+
x+=+%281+%2B-+sqrt%28+1-%28-812%294+%29%29%2F%282%29+
x+=+%281+%2B+sqrt%283249+%29%29%2F%282%29+ x+=+%281+-+sqrt%283249+%29%29%2F%282%29+
x+=+%281+%2B+57%29%2F%282%29+ x+=+%281+-+57%29%2F%282%29+
x+=+%2858%29%2F%282%29+ x+=+%28-56%29%2F%282%29+
x+=+29+ x+=+-28+
The first number is -28 and second number is 29

Answer by Alan3354(69443) About Me  (Show Source):