Answer:
24.98 units
Step-by-step explanation:
The picture of the question in the attached figure
we have the coordinates
P(1,-6),D(4,3),O(7,-6)
The perimeter of triangle OPD is equal to
the formula to calculate the distance between two points is equal to
step 1
Find the distance OP
we have
O(7,-6),P(1,-6)
substitute in the formula
step 2
Find the distance PD
we have
P(1,-6),D(4,3)
substitute in the formula
step 3
Find the distance OD
we have
O(7,-6),D(4,3)
substitute in the formula
step 4
Find the perimeter
Question 21
Let's complete the square
y = 3x^2 + 6x + 5
y-5 = 3x^2 + 6x
y - 5 = 3(x^2 + 2x)
y - 5 = 3(x^2 + 2x + 1 - 1)
y - 5 = 3(x^2+2x+1) - 3
y - 5 = 3(x+1)^2 - 3
y = 3(x+1)^2 - 3 + 5
y = 3(x+1)^2 + 2
Answer: Choice D
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Question 22
Through trial and error you should find that choice D is the answer
Basically you plug in each of the given answer choices and see which results in a true statement.
For instance, with choice A we have
y < -4(x+1)^2 - 3
-7 < -4(0+1)^2 - 3
-7 < -7
which is false, so we eliminate choice A
Choice D is the answer because
y < -4(x+1)^2 - 3
-9 < -4(-2+1)^2 - 3
-9 < -7
which is true since -9 is to the left of -7 on the number line.
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Question 25
Answer: Choice B
Explanation:
The quantity (x-4)^2 is always positive regardless of what you pick for x. This is because we are squaring the (x-4). Squaring a negative leads to a positive. Eg: (-4)^2 = 16
Adding on a positive to (x-4)^2 makes the result even more positive. Therefore (x-4)^2 + 1 > 0 is true for any real number x.
Visually this means all solutions of y > (x-4)^2 + 1 reside in quadrants 1 and 2, which are above the x axis.
A door alarm works in 72 out of 100 cases.
surveillance camera works in 68 out of 100 cases.
The probability that method A is used = 72/100
The probability that method B is used = 68/100
Since both method are used we find the probability of A and B
Probability ( A and B) = *
=
32*1.2=38.4 (.2 is the 20%, and the 1 adds the percent to the original cost making it a mark up)
You want the average?
add them all together and then divided by the number of events