Hints on Homework:
#9: 5x^2 - 20x = 10 -- move the 10 to the left hand side of the equation and then factor out a five.
5(x^2 - 4x - 2) = 0 Then complete the square using the terms inside of parentheses. Just don't forget about the factor of five!!
5 [(x^2 - 4x + ___) - 2 - ___] = 0
5[(x^2 -4x + 4) -2 - 4] = 0
5[(x-2)^2 - 6] = 0 Therefore the factor inside the brackets must be equal to zero, since the only other factor is five.
(x-2)^2 =6 -- now use the square root rules from there.
#11: x^2 - 5x = 2 -- move the 2 to the left hand side of the equation. Then use completing the square as show in class.
(x^2 - 5x + ____) - 2 - _____ =0
#13: x^2 - 12x +35 = 0
(x^2 -12x + ____) +35 - ____ = 0 Remember (b/2)^2!!
Hope the above tips help!
Feel free to check out this instructional video as well if you still have questions:
Completing the Square Instructional Video (easy problem)
Completing the Square Instructional Video #2 (harder problem)
Feel free to check out this instructional video as well if you still have questions:
Completing the Square Instructional Video (easy problem)
Completing the Square Instructional Video #2 (harder problem)
