SOLUTION: Please help me slove this quadratic equation: In two-digit number, the tens digit is 5 less than the ones digit. The number is 14 greater than the product of the digits. Find the n

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Question 468789: Please help me slove this quadratic equation: In two-digit number, the tens digit is 5 less than the ones digit. The number is 14 greater than the product of the digits. Find the number.
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
Let x is the tens digit
Let y is the ones digit
Then number is 10x%2By
the tens digit is 5 less than the ones digit, then y-x=5.
The number is 14 greater than the product of the digits, then 10x%2By-xy=14
The system of equations
system%28y-x=5%2C10x%2By-xy=14%29
Use the substitution method
From the first equation y=5%2Bx
10x%2B%285%2Bx%29-x%285%2Bx%29=14
10x%2B5%2Bx-5x-x%5E2-14=0
x%5E2-6x%2B9=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-%28-6%29+%2B-+sqrt%28+%28-6%29%5E2-4%2A1%2A9+%29%29%2F%282%2A1%29+
x+=+%286+%2B-+sqrt%28+0%29%29%2F2+
x=3 the tens digit
y=5%2B3=8 the ones digit
The number is 38