Answer:
The number would have to be added is 2
Step-by-step explanation:
To find the form of the completing square of the quadratic function:
- Divide the coefficient of x by 2
- Subtract the numerical term from the square of the quotient
Let us do these steps with our question
∵ x² - 2x - 1 = 0
→ Divide the coefficient of x by 2
∵ The coefficient of x is -2
∴ -2 ÷ 2 = -1
→ Square the -1
∵ (-1)² = 1
→ Subtract the numerical term from 1
∵ The numerical term = -1
∵ 1 - (-1) = 1 + 1 = 2
∴ We must add 2 to -1 to get 1
→ (x² - 2x - 1 + 2) - 2 = 0
→ (x² - 2x + 1) = 2
→ (x - 1)² = 2
The number would have to be added is 2
The surest way to get many of the points needed to plot a quadratic is to use the quadratic formula. This will give the roots (real or imaginary). It will give you the completed square form also called the vertex form (if you know how to use the discriminant). It can easily give you the y intercept (which you can find before you use the quadratic formula). It gives the max or min upon solution.
The easiest one to use if it is available to you, is factoring. The quadratic may not be factorable. But if it is and you can see it, then this gives you 2 points immediately (the roots) and a third without much trouble (the y intercept). Factoring will also give you the x value of the vertex. (Find the average between the 2 roots)
This needs an example
Suppose you have y = (x - 5)(x - 9) The roots are 5 and 9, correct? So the x value of the vertex is (5 + 9)/2 = 7 It always works.
Completing the square always gives you the minimum or maximum right away. For example if you have y = (x - 2)^2 - 5 it means you have the vertex at (2,-5) You can get the roots easily enough. So this form is useful, but not as sure as the quadratic equation or as simple as factoring.
Graphing is the most certain way to check your answer. I find it the most useful thing to do with modern computers. There are all sorts of things that a graph will reveal that algebra by itself might be laborious and prone to leading you to mistakes. Graphing tends to correct that problem.
Answer:
by getting the solution
Step-by-step explanation:
Answer:
3.75p+8.50<=34.75
Step-by-step explanation:
No matter what, if you get at least 2 pair of flip flops you will be spending $8.50 plus 3.75 per pair on each additional pair . If she has $34.75 to spend and cannot go over, the inequality sign will be less than or equal to. It is fine if she spends less than that and it's ok if she spends exactly that, but she cannot spend more than she has.
The inequality then would be this:
3.75p+8.50<=34.75....
