Question

If using the method of completing the square to solve the quadratic equation x^2-15x-10=0, which number would have to be added to complete the square

Answer 1

`\bold{\frac{225}4}`

Explanation:

`x^2-15x-10=0\\\\x^2-2\cdot x\cdot\frac{15}2+(\frac{15}2)^2-(\frac{15}2)^2-10=0\\\\(x-\frac{15}2)^2-\frac{225}4-10=0`

So to complete the square we need to add (and subtract) the number
`\frac{225}4`