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Liam is older than Chloe, and their ages are consecutive integers. Find Liam's age if the sum of the square of Liam's age and 5 times Chloe's age is 121.

A. 7
B. 8
C. 6
D. 9

User Sramu
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1 Answer

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Final answer:

Liam's age can be determined by setting up and solving a quadratic equation based on the given conditions. Chloe's age is represented as x, and Liam's age is x + 1. After solving, we find that Liam is 9 years old.

Step-by-step explanation:

We are given that Liam's age and Chloe's age are consecutive integers and that Liam is older than Chloe. Let's denote Chloe's age as x and thus Liam's age is x + 1. The problem tells us that the sum of the square of Liam's age and 5 times Chloe's age equals 121. This leads to the following equation:

(x + 1)^2 + 5x = 121

Now we can solve this quadratic equation:

x^2 + 2x + 1 + 5x = 121

x^2 + 7x + 1 = 121

x^2 + 7x + 1 - 121 = 0

x^2 + 7x - 120 = 0

To solve this, we look for factors of -120 that add up to 7. The factors -8 and 15 come to mind.

x^2 - 8x + 15x - 120 = 0

(x - 8)(x + 15) = 0

This gives us two possible solutions for x:

x = 8 or x = -15

We can disregard -15, as ages cannot be negative. Therefore, Chloe is 8 years old and Liam, being one year older, is 9 years old. So, the correct answer is D. 9.

User Linguist
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