Firstly, simplife the function in the following way:
.
There are three x-intercepts: x=-1; x=2 and x=-2 (therefore, options A and D are incorrect).
Since before brackets is sign "-", you should state that graph starts down on the left (you can check this substituting smaller negative number than -2 into function expression. For example, if x=-10, then f(-10)=-(-10+2)(-10+1)(-10-2)=-(-8)(-9)(-12)>0) and goes up on the right (you can check this substituting greater positive number than 2 into function expression. For example, if x=10, then f(-10)=-(10+2)(10+1)(10-2)=-(12)(11)(8)<0).
Answer: correct choice is B.
We are given area of the ribbon = 144 square inches.
We know formula for side of a square = .
Plugging value of area in the formula, we get
Side of the square
= 12 inches.
Sonya wants to sew ribbon along each side of a square pillow.
So, we need to find the perimeter of the square pillow.
<h3>Perimeter = 4 × side = 4 × 12 = 48 inches.</h3><h3>Therefore, she buy 48 inches of ribbon to have the exact amount that she needs.</h3>Like you said, we need to use <u><em>substitution</em></u> to solve for y.
Now that we've solved for y, we can plug in the number we got into one of the <u><em>original</em></u> equations. (You can choose either equation, but I will use the first one.)
Now we have the solution of this system.