How do you solve x2+9=10x?

2 Answers
Apr 11, 2016

1 and 9

Explanation:

y=x210x+9=0.
Find 2 real roots, knowing sum (-b = 10) and product (c = 9).
They are 1 and 9.

Apr 11, 2016

9,1

Explanation:

x2+9=10x

Subtract 10x both sides

x2+910x=10x10x

x2+910x=0

Rewrite the equation in Standard form (ax2+bx+c=0)

x210x+9=0

This is a Quadratic formula

x=b±b24ac2a

Remember that aandb are the coefficients and c is the constant

So,

a=1

b=10

c=9

x=(10)±1024(1)(9)2(1)

x=10±100(36)2

x=10±642

x=10±82

x=105±8421

x=5±4

Remember that ± means "plus or minus",

Which implies that,

x=5+4=9

x=54=1

¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|x=9,1|−−−−−−

If you are confused with the Quadratic formula

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