If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content

Strategy in solving quadratics


Esma and Hunter were trying to solve the equation:
x, squared, plus, 8, x, equals, 2, x, minus, 8
They both agreed they should first subtract 2, x and add 8 to both sides and rewrite the equation as x, squared, plus, 6, x, plus, 8, equals, 0.
Then Esma said, "I can complete the square. I can add 1 to both sides to rewrite this equation as x, squared, plus, 6, x, plus, 9, equals, 1, factor, and solve using square roots."
Hunter said, “I'll factor the left-hand side of the equation as left parenthesis, x, plus, 2, right parenthesis, left parenthesis, x, plus, 4, right parenthesis and solve using the zero product property.”
Whose solution strategy would work?
Choose 1 answer: