Answer:
D. 98 ft.^2
Step-by-step explanation:
A= b*h
=13*8
=104 ft.^2
Because there is a piece missing, we know it must be under 104 ft.^2. They didn't give us enough information to find the complete area of the missing triangle, so I used the process of elimination. With the responses given and this information, we can assume that the answer is 98 ft.^2.
Using the triangle, we can find the angle lengths and using those and trig ratios, find the side lengths. Lets say the top side length is "y".
Using the Law of triangles, we can find the missing angle from 180-90-70=20 deg.
Then we can use the Law of sines,
sin(70)/13=sin(20)/y
y=sin(20)*13/sin(70)
y=15.34
Finally, we use the Pythagorean Theorem, (13)^2+(15.34)^2=x^2
x = 20.1
The probability any one system works is 0.99
So the probability of any one system failing is 1-0.99 = 0.01, so basically a 1% chance of failure for any one system
Multiply out the value 0.01 with itself four times
0.01*0.01*0.01*0.01 = 0.000 000 01
I'm using spaces to make the number more readable
So the probability of all four systems failing is 0.00000001
Subtract this value from 1 to get
1 - 0.00000001 = 0.99999999
The answer is 0.99999999 which is what we'd expect. The probability of at least one of the systems working is very very close to 1 (aka 100%)
To find X, we can divide 5 into 40.
40 divided by 5 is 8.
Now we can do 5 x 8. That is 40.
X=40
OR we can do it another way.
40 divided by 5 is 8.
Cross out 5 divided by 5.
Now we have 8. Still.
X is 8