QuestionSolve the polynomial inequality and graph the solution notation.
13)
Studdy Solution
STEP 1
What is this asking?
Find the range of where is less than or equal to zero, and then draw a picture of that range on a number line!
Watch out!
Don't forget to check if the parabola opens upwards or downwards, this changes everything!
Also, remember to include the endpoints where the quadratic equals zero, since the problem says "less than *or equal to* zero".
STEP 2
1. Factor the quadratic
2. Find the roots
3. Determine the sign of the quadratic
4. Write the solution and graph it
STEP 3
Let's **factor** our quadratic expression .
We're looking for two numbers that **multiply** to and **add** to .
Those magic numbers are and !
STEP 4
So, we can rewrite our quadratic as .
Factoring helps us see where the quadratic equals zero, which is super important for solving inequalities!
STEP 5
Now, let's find where our factored quadratic equals zero.
This happens when either or .
STEP 6
If , then adding to both sides gives us .
If , then adding to both sides gives us .
These are our **roots**, also known as the **zeros** of the quadratic!
STEP 7
Our parabola opens *upwards* because the coefficient of is positive (it's ).
This means the quadratic is *negative* *between* the roots and *positive* *outside* of the roots.
STEP 8
We want to know where , meaning where the quadratic is less than or equal to zero.
Since it's less than zero *between* the roots, our solution will be the interval between our roots, including the roots themselves!
STEP 9
Our roots are and .
Since we're looking for where the quadratic is less than or equal to zero, our solution is .
This means can be any number from to , inclusive!
STEP 10
To graph this, draw a number line, put filled-in circles at and (because they're included in the solution), and shade the region between them.
This shaded region visually represents all the values that make our inequality true!
STEP 11
The solution to the inequality is .
The graph is a number line with closed circles at and , and the region between them shaded.
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