Find the maximum/minimum value of the quadratic function x2 – 10x = y + 40 by completing the square method.
+33614 Find the maximum/minimum value of the quadratic function x2 – 10x = y + 40 by completing the square method.
x2 - 10x = y + 40
Add 25 to both sides:
x2 - 10x + 25 = y + 65
Now the LHS can be written as:
(x - 5)2 = y + 65
Subtract 65 from both sides:
y = (x - 5)2 - 65
The minimum occurs when x = 5, at which point y = -65.
