Answer:
C. 128 in²
Step-by-step explanation:
We know that the opposite sides of rectangles are congruent, so 8 = 2x. If we divide 8 by 2 and 2x by 2, we get x = 4.
- This means that the other side length, (3x + 4), equals 3(4) + 4 = 12 + 4 = 16 inches
Now, the area of a rectangle is l × w, where l = length and w = width. The dimensions of this rectangle are 8 and 16, so 8 × 16 = 128 in².
<u>Answer: </u>
If they worked together it would take 4 hours for the machines to produce 100 widgets
<u>Step-by-step explanation:</u>
w = widgets hr = hour ph = per hour
Old machine - 50w = 5hr = 10ph
New machine - 30w = 2hr = 15ph
Old machine - 20w = 2hr
New machine - 30w = 2hr
<h3>Together - 50w = 2hr x 2 </h3><h3> Final: 100w = 4hr</h3>
I hope this helped!
Answer:
x+3
Step-by-step explanation:
Area of a rectangle is 
.
We know the width, W, is 
and we know the area is 
.
Inputting this in our formula above we get:
L is a an expression such that when you multiply it to 
gives you 
.
is a difference of squares and can be factored using:
.
.
So L=x-3 and W=x+3.
<h3>3
Answers:</h3>
A) y intercept is (0,3)
C) Axis of symmetry is x = -1
D) Vertex is (-1, 4)
So basically everything but choice B is true.
========================================
Explanation:
Choice A is true because plugging in x = 0 leads to y = 3. Effectively, anything with an x goes away when x = 0 leaving that 3 behind. So finding the y intercept in this form is fairly fast.
-------------------
To check choices B through D, let's convert the equation into vertex form.
y = -1x^2 - 2x + 3 is in the form y = ax^2 + bx + c where
a = -1
b = -2
c = 3
The vertex is located at (h,k) such that h = -b/(2a)
Plug the values of 'a' and 'b' into the equation below
h = -b/(2a)
h = -(-2)/(2*(-1))
h = 2/(-2)
h = -1
The x coordinate of the vertex is x = -1
Then use this to find the y coordinate of the vertex
y = -1x^2 - 2x + 3
y = -1(-1)^2 - 2(-1) + 3
y = 4
The y coordinate of the vertex is 4, meaning k = 4
The vertex overall is (h,k) = (-1, 4)
This shows choice D is true, meaning choice B has to be false.
Choice C is true because the axis of symmetry is the x coordinate of the vertex. This is the vertical line that cuts the parabola into two mirrored halves. This vertical line always goes through the vertex.
You have to estimate the slope of the tangent line to the graph at <em>t</em> = 10 s. To do that, you can use points on the graph very close to <em>t</em> = 10 s, essentially applying the mean value theorem.
The MVT says that for some time <em>t</em> between two fixed instances <em>a</em> and <em>b</em>, one can guarantee that the slope of the secant line through (<em>a</em>, <em>v(a)</em> ) and (<em>b</em>, <em>v(b)</em> ) is equal to the slope of the tangent line through <em>t</em>. In this case, this would be saying that the <em>instantaneous</em> acceleration at <em>t</em> = 10 s is approximately equal to the <em>average</em> acceleration over some interval surrounding <em>t</em> = 10 s. The smaller the interval, the better the approximation.
For instance, the plot suggests that the velocity at <em>t</em> = 9 s is nearly 45 m/s, while the velocity at <em>t</em> = 11 s is nearly 47 m/s. Then the average acceleration over this interval is
(47 m/s - 45 m/s) / (11 s - 9 s) = (2 m/s) / (2 s) = 1 m/s²
