There are two numbers with the following properties. 1) The second number is 3 more than the first number. 2) The product of the two numbers is 9 more than their sum. Which of the following repressents possible values of these two numbers.
A. -6, -3,
B. -4,-1
C. -1, 4
D. -3, 6
A. -6, -3,
B. -4,-1
C. -1, 4
D. -3, 6
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one number is x, the other is x+3
the product is x(x+3)
the sum is 2x + 3
apply 2)
x(x+3) = 2x + 3 + 9
x^2 + 3x - 2x - 12 = 0
x^2 + x - 12 = 0
(x+4)(x-3) = 0
x = -4 or x = 3
not sure how this fits ABCD you asked for
the product is x(x+3)
the sum is 2x + 3
apply 2)
x(x+3) = 2x + 3 + 9
x^2 + 3x - 2x - 12 = 0
x^2 + x - 12 = 0
(x+4)(x-3) = 0
x = -4 or x = 3
not sure how this fits ABCD you asked for
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From statement (1), we have y = 3 + x
From statement (2), we have xy = 9 + x + y
Substituting for y in statement (2), we have
x(3+x) = 9 + x + 3 + x
3x + x^2 = 2x + 12
x^2 + 3x - 2x - 12 = 0
x^2 + x - 12 = 0
(x+4)(x-3) = 0
x = -4 or x = 3
B is the only choice that uses one of these as the smaller number.
Jen
From statement (2), we have xy = 9 + x + y
Substituting for y in statement (2), we have
x(3+x) = 9 + x + 3 + x
3x + x^2 = 2x + 12
x^2 + 3x - 2x - 12 = 0
x^2 + x - 12 = 0
(x+4)(x-3) = 0
x = -4 or x = 3
B is the only choice that uses one of these as the smaller number.
Jen
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If x is the first x+3 is the second. Their product is x(x+3) so x(x+3) = x+(x+3)+9.
which becomes x^2 + x - 12 =0 or (x+4)(x-3)=0 means x= -4 or 3
But no alternative matches with this answer. Funny!
which becomes x^2 + x - 12 =0 or (x+4)(x-3)=0 means x= -4 or 3
But no alternative matches with this answer. Funny!
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First number be x
Second number = x+3
x ( x+3) = x + ( x+ 3) + 9
x^2 + 3x = 2x + 12
x^2 + x -12 = 0
( x + 4) ( x-3) = 0
x = -4 Or 3
Second number = x+3
x ( x+3) = x + ( x+ 3) + 9
x^2 + 3x = 2x + 12
x^2 + x -12 = 0
( x + 4) ( x-3) = 0
x = -4 Or 3