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Half of the product of two consecutive numbers is 105. which equation can be used to solve for n, the smaller of the two numbers

User Felixbr
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2 Answers

4 votes

Answer:

The numbers are n and n + 1

Average = Av = 105

Explanation:

User Maxflow
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7.3k points
5 votes

Givens

The numbers are n and n + 1

Average = Av = 105

Equation

Av = (n)(n + 1)/2

Solution

Av = 105

n(n +1)/2 = 105 Multiply both sides by 2

n(n + 1) = 105 * 2

n(n + 1) = 210 Remove the brackets.

n^2 + n = 210 Subtract 210 from both sides

n^2 + n - 210 = 0

factor

(n+15)(n - 14)

n + 15 = 0

n = - 15

n = - 15 which is the smallest of the two answers.

n + 1 = - 14

Check

(-15)*(-14)/2 =

210/2

105 It does check.

User Ranguard
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7.7k points