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An integer is 7 more than 2 times another. If the product of the two integers is 60, then find the integers.

User Winters
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1 Answer

4 votes

Answer:

15 and 4

Explanation:

Let the first integer be x and the second integer be y. If the first integer is 7 more than 2 times another, then x = 7+2y

The two integers will be y and 7+2y. If the product of both integers is 60, then;

y(7+2y) = 60

7y + 2y² = 60

2y² + 7y -60 = 0

2y²-8y+15y-60 = 0

2y(y-4)+15(y-4) = 0

(2y+15)(y-4) = 0

2y+15= 0 and y-4 = 0

2y = -15 and y = 4

y = -15/2 and 4

Taking the positive integer, y = 4

To get the other integer, we will substitute y = 4 into the equation x = 7+2y;

x = 7+2(4)

x = 7+8

x = 15

Hence the two integrs are 15 and 4

User Wiredmark
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