Answer:
c. 4x + 20 = 140
Step-by-step explanation:
Perimeter = 140 feet
Width = L + 10
P = 2w + 2L
P = 2(L + 10) + 2L
P = 2L + 20 + 2L
P = 4L + 20
The function is graphed as shown below
Part A:
We use the formula

to find the vertex of the function. A quadratic function of the form of

and equating this form to the given function

, we have

and

.
Substituting

and

into the vertex formula, we have

, as shown in the graph
This calculation means that the highest profit is achieved when the number of photo printed equals to ten photos
Part B:
We can find solution to this equation by factorising





and

, as shown in the graph
The two values means that the company makes no profit when they either produce 5 or 15 photos
The value of the length DF is 1/4 of that of CD because of the Angle Bisector Theorem for triangles.
<h3>
What is the Angle Bisector Theorem?</h3>
The Angel Bisector Theorem states that if a ray bisects an angle of a triangle, it dissects the side of the triangle that is opposite to the dissected angle into parts that are proportionate to the adjacent sides.
Note that the angle that has been dissected here is ∠CBD. Thus,
= 
See the link below for more about Angle Bisector Theorem of the Triangle:
brainly.com/question/21475560
<em>f(3) = 13</em>
- Step-by-step explanation:
<em>f(x) = 2x + 7</em>
<em>replace </em><em>x</em><em> with </em><em>3</em>
<em>f(3) = 2×3 + 7</em>
<em>= 6 + 7</em>
<em>= 13</em>
Answer:
20.4cm²
Step-by-step explanation:
base= 10.2
height= 2
10.2×2=20.4cm²