your stupid........................................................................
<span>4x^2 - 25
= (2x)^2 - 5^2 .................using a^2 - b^2 = (a+b)(a-b)
= (2x + 5)(2x - 5)</span>
The minimum value of a function is the place where the graph has a vertex at its lowest point.
There are two methods for determining the minimum value of a quadratic equation. Each of them can be useful in determining the minimum.
(1) By plotting graph
We can find the minimum value visually by graphing the equation and finding the minimum point on the graph. The y-value of the vertex of the graph will be the minimum.
(2) By solving equation
The second way to find the minimum value comes when we have the equation y = ax² + bx + c.
If our equation is in the form y = ax^2 + bx + c, you can find the minimum by using the equation min = c - b²/4a.
The first step is to determine whether your equation gives a maximum or minimum. This can be done by looking at the x² term.
If this term is positive, the vertex point will be a minimum; if it is negative, the vertex will be a maximum.
After determining that we actually will have a minimum point, use the equation to find it.
For question 4: you have to do (y2 - y1) divided by (x2 - x1) to get the rise over run...
5-2
——. = 3/4
11 - 7
For question 5: input the values of x,y and the gradient into the equation of a line.....
y = mx+ c
-8 = 3(-2) + c
-8 = -6 + c
-2 = c
therefore:
y = 3x - 2
Hope this helps! Any questions let me know :)
