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42 votes
What is the greatest solution of x in the equation x2 + 5x – 14 = 10?

User Jerad Rose
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1 Answer

10 votes
10 votes

Answer:

x = 3

Explanation:

First, make the equation equal to zero by subtracting 10 from both sides

x² + 5x - 24 = 0

Now we have to factor this

To factor this, we basically have to find two numbers where they multiply to equal -4 and add up to 5

Those numbers are 8 and -3

8 x -3 = -24

8 - 3 = 5

This leads us to this equation: (x + 8)(x - 3) = 0

x - 3 = 0

x + 8 = 0

Isolate the x in both equations

x - 3 = 0

+ 3 + 3

x = 3

x + 8 = 0

- 8 - 8

x = -8

This means x can be 3 or -8 for the equation to be true, but we have to pick the greatest number. So it's 3 since it's the biggest.

User Haukex
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