Answer:
15.71
Step-by-step explanation:
To find the radius, half the diameter because r x 2 = diameter. 5/2 = 2.5
Put in circumference formula C=2πr
c=2 x 3.14 x 2.5
c= 2 x 7.85
c=15.7
Put the value into the circle circumference formula C=2πr
Answer:
30.7 ft
Step-by-step explanation:
<em>An equilateral triangle with area 43.5 has a height of 8.68 not 8.5</em>
<em>I will do the problem as written even though it is not a possible equilateral triangle</em>
<em>---------------------------------------------</em>
a = (1/2)bh
43.5 = (1/2)b(8.5)
43.5 = 4.25b
b = 43.5/4.25
b = 10.2352941176
-----------------------
p = 3b
p = 3 * 10.2352941176
p = 30.7058823528
~ 30.7 ft
For the first one it is the fourth one 15/x
(16x^2+4x-4x-1)-3=15x^2
16x^2-1-3=15x^2
16x^2-4=15x^2
X^2=4
X=+or-2
<h3>
Answer: Choice B</h3><h3>
y = x^2 + 7x + 1</h3>
======================================
Proof:
A quick way to confirm that choice B is the only answer is to eliminate the other non-answers.
If you plugged x = 1 into the equation for choice A, you would get
y = -x^2 + 7x + 1
y = -1^2 + 7(1) + 1
y = -1 + 7 + 1
y = 7
We get a result of 7, but we want 9 to be the actual output. So choice A is out.
-----------
Repeat for choice C. Plug in x = 1
y = x^2 - 7x + 1
y = 1^2 - 7(1) + 1
y = 1 - 7 + 1
y = -5
We can eliminate choice C (since again we want a result of y = 9)
-----------
Finally let's check choice D
y = x^2 - 7x - 1
y = 1^2 - 7(1) - 1
y = 1 - 7 - 1
y= -7
so choice D is off the list as well
-----------
The only thing left is choice B, so it must be the answer. It turns out that plugging x = 1 into this equation leads to y = 9 as shown below
y = x^2 + 7x + 1
y = 1^2 + 7(1) + 1
y = 1 + 7 + 1
y = 9
And the same applies to any other x value in the table (eg: plugging in x = 3 leads to y = 31, etc etc).
