# Solve x2 - 8x + 5 = 0 using the completing-the-square method.

**Solution:**

Given x^{2} - 8x + 5 = 0

x^{2} - 8x = -5

Here a = 1, b = -8 and c = 5

We make a perfect square trinomial using completing the square method.

In order to make it a perfect square, we need to add (b/2)^{2} on both sides: (-8/2)^{2} = 16

x^{2} - 8x +16 = -5 + 16

x^{2} - 2(x)(4) + 4^{2} = 11

We know that a^{2 }- 2ab + b^{2} = (a - b)^{2}

(x - 4)^{2} = 11

x - 4 = ±√11

x = 4 + √11 or x = 4 - √11

## Solve x^{2} - 8x + 5 = 0 using the completing-the-square method.

**Summary:**

By solving x^{2} - 8x + 5 = 0 using the completing-the-square method, we got x = 4 + √11 or x = 4 - √11

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