Answer:
- It is the last graph: solid line, shaded area over the line x = 2 - x/2
Explanation:
1) <u>Set the algebraigic expression that represents the combinations of sofa and pillow orders:</u>
- Number of sofas: x (given)
- Number of pillows: 2y (given, since they come in pairs)
- Number of items = number of sofas + number of pillows = x + 2y
- Minimum of 4 items in each order (given) ⇒ x + 2y ≥ 4
<u>2) Predict the graph of the inequality x + 2y ≥ 4</u>
- The border line is the equation x + 2y = 4
- You can choose two points to draw a line
- Choose the axis-intercepst:
x = 0 ⇒ 2y = 4 ⇒ y =4/2 ⇒ y = 2 ⇒ point (0,2)
y = 0 ⇒ x = 4 ⇒ point (4,0)
Then the lines goes through (0,2) and (4,0) ... [the four graphs meet this]
- The shading area is above the line because when you solve for y you get y ≥ 2 - x/2, and the line is included because the "equal to" part of the symbol (≥ means greater than or equal to).
- To state that the line is included the graph uses a continous line instead of a dotted one.
<u>3) Conclusion:</u>
That means that the correct graph is the last one: solid line, shaded area over the line y = 2 - x/2.
Note: a more detailed graph would include the fact that the items cannot be negative, i.e. x ≥ 0 and y ≥ 0, which would result in that the shaded area would be on the first quadrant.
Four thousand one hundred eighty
You have the correct answer. Nice work. If you need to see the steps, then see below
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First we need to find the midpoint of H and I
The x coordinates of the two points are -4 and 2. They add to -4+2 = -2 and then cut that in half to get -1
Do the same for the y coordinates: 2+4 = 6 which cuts in half to get 3
So the midpoint of H and I is (-1,3). The perpendicular bisector will go through this midpoint
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Now we must find the slope of segment HI
H = (-4,2) = (x1,y1)
I = (2,4) = (x2,y2)
m = (y2 - y1)/(x2 - x1)
m = (4 - 2)/(2 - (-4))
m = (4 - 2)/(2 + 4)
m = 2/6
m = 1/3
Flip the fraction to get 1/3 ---> 3/1 = 3
Then flip the sign: +3 ----> -3
So the slope of the perpendicular bisector is -3
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Use m = -3 which is the slope we found
and (x,y) = (-1,3), which is the midpoint found earlier
to get the following
y = mx+b
3 = -3*(-1)+b
3 = 3+b
3-3 = 3+b-3
0 = b
b = 0
So if m = -3 and b = 0, then y = mx+b turns into y = -3x+0 and it simplifies to y = -3x
So that confirms you have the right answer. I've also used GeoGebra to help confirm the answer (see attached)
A= base x height = 3x4 = 12 ft