We have the following:

solving for x

The solution of x is equal to 28, therefore 12 is not a solution of the equation
Answer:
diameter of the pizza = 21.88 centimeters
Step-by-step explanation:
Given:
C = d^2 – 2d + 447
where
C = cost of the pizza
d = diameter of the pizza
If the pizza costs $12.00, then what is a reasonable estimate for the diameter of the pizza?
12 = d^2 – 2d + 447
d^2 - 2d = 447 - 12
d^2 - 2d = 435
d^2 - 2d - 435 = 0
Solve the quadratic equation using formula
a = 1
b = -2
c = -435
d = -b +or- √b^2 - 4ac / 2a
= -(-2) +or- √(-2)^2 - (4)(1)(-435) / 2(1)
= 2 +or- √4 - (-1740) / 2
= 2 +or- √4 + 1740 / 2
= 2 +or- √1744 / 2
= 2 +or- 4√109 / 2
= 2/2 +or- 4√109/2
= 1 +or- 2√109
d = 1 + 2√109 or d = 1 - 2√109
= 1 + 2(10.44) or d = 1 - 2(10.44)
= 1 + 20.88 or d = 1 - 20.88
d = 21.88 or -19.88
diameter of the pizza = 21.88 centimeters
Therefore, the estimated diameter of the pizza can not be negative. So, diameter of the pizza = 21.88 cm
Answer:
4 16 2.000
5 25 2.236
6 36 2.449
7 49 2.646
Step-by-step explanation:
The question is telling you that the length of the rectangle is 3 metres more than twice the width.
So let:
<em>w= width</em>
<em>L= length</em>
Because the length is 3 metres more than twice<em> </em>the width: <em>L= </em><em>2</em><em>w+</em><em>3</em>
They also tell you the perimeter is 48 metres.
<em>P= L+L+w+w</em>
So the equation of the perimeter is:
<em>48= (2w+3)+(2w+3)+2w +2w</em>
<em>48= 2(2w+3) + 4w</em>
To find w, expand and simplify.
<em>48= 4w+6+4w</em>
<em>48= 8w + 6</em>
<em>42= 8w</em>
<em>5.25=w</em>
Now that you know the width, plug in the value into the length equation:
<em>L= 2w+3</em>
<em>L=2(5.25)+3</em>
<em>L=10.50+3</em>
<em>L=13.5</em>
If I am wrong let me know! I hope this helps.
Answer:
Step-by-step explanation: