Science

Math

Humanities

... and beyond

Socratic Meta
Featured Answers

Topics

How do you solve #x^2 - 18x = 19# by completing the square?

↳Redirected from "Can mixtures be separated by chromatography?"

1 Answer

Jul 13, 2015

Solve: #y = x^2 - 18x - 19 = 0#

Explanation:

Since (a - b + c = 0), use the shortcut. The 2 real roots are: (- 1) and (-c/a = 19).

Solving by completing the squares

#x^2 - 18x + 81 = 19 + 81 = 100#
#(x - 9)^2 = 100# --> #x - 9 = +- 10#
#x = 9 +- 10# --> x = - 1 and x = 19.

Related questions

See all questions in Completing the Square

Impact of this question

4461 views around the world

You can reuse this answer
Creative Commons License