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The product of two consecutive integers is 420. An equation is written in standard form to solve for the smaller integer by factoring

2 Answers

2 votes

Answer:

X * (X +1) = 420

X^2 + X = 420

X^2 + X -420 = 0

X = 20

Explanation:

User Alexey Chuhrov
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5 votes

For this case we have
20 * 21 = 420. We must find an equation that allows us to find the smallest value. So:

Let "x" be the variable that represents the smallest number. Thus, "x + 1" represents the consecutive integer. The equation would be given by:


x * (x + 1) = 420\\x ^ 2 + x = 420\\x ^ 2 + x-420 = 0

To factor, we must find two numbers that multiply as a result -420 and sum as a result 1.

These numbers are:


21, -20\\21-20 = 1\\21 * (-20) = -420

Thus, the factorization is:


(x-20) (x + 21) = 0

The roots are:


x = 20\\x = -21

Effectively, the smallest integer was found,
x = 20.

Answeer:


x ^ 2 + x-420 = 0\\(x-20) (x + 21) = 0

User Hertzel Guinness
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5.7k points