Answer:
10.2cm
Step-by-step explanation:
Perimeter is the sum of the lengths of all sides.
1st side: 9cm
2nd side: 7.8cm
Perimeter: 27cm
Perimeter = 1st + 2nd +3rd side of a triangle
27cm = 9cm +7.8cm + 3rd side
3rd side = 27cm - 9cm -7.8cm
= 10.2cm
Answer: (2,2)
Step-by-step explanation:
I'm going to use substitution to solve this:
First, I use the second equation to solve for y in terms of x.
2x - y = 2
-y = 2 - 2x
y = 2x - 2
Then, I plug the value for y into the first equation:
2x + 4y = 12
2x + 4(2x - 2) = 12
2x + 8x - 8 = 12
10x - 8 = 12
10x = 20
x = 2
Now that we have x, we can plug it into either equation (I used the first) to get the value for y:
2x + 4y = 12
2(2) + 4y = 12
4 + 4y = 12
4y = 8
y = 2
We get the point (2,2) as a solution.
Note: This is the point where both lines intersect.
I guess ur just gunna have to bear with whatever until we have a multiple choice answer selection.
Answer:

Step-by-step explanation:
From the question we are told that
Mean
Standard deviation 
Percentage for men =99.75%
Generally the empirical rule 68%,95% and 99.7% of data value lay b/w 1,2,3 standard deviation of mean
Standard deviation n= 9
Mean x= 120
Generally the interval of systolic blood pressure for middle 99.7 of male G is mathematically given as



Answer: (-3,-2)
Step-by-step explanation: