Answer:
the answer is A. it good answer
Find attached a graph that I constructed.
To do that graph I used Excel.
First I did a table with this set of points:
<span><span><span>height presuure
</span>
<span>
miles psi
</span>
<span>
0
14,7
</span>
<span>
<---- initial data
3.6 7.35
</span>
<span>
<--- increase hegiht 3.6 miles => half pressure
7.2
3.675
</span>
<span>
<---- second increase of 3.6 miles in height
10. 8
1.8375
</span>
<span>
<---- third increase of 3.6 miles in height
14.4
0.91875
</span>
<span>
18 0.459375
</span>
</span></span>
Answer:
x=# of boys
x+7=# of girls
x+x+7=25
2x+7=25
2x=25-7
2x=18
x=18/2
x=9 boys
x+7=16 girls
If you don't understand variables use trial and error.
Boys Girls
1 8
2 9
3 10
4 11
5 12
6 13
7 14
8 15
9 16 9+16=25 students
You could start this way...
Boys Girls
12 13
11 14
10 15
9 16 16 is 7 more than 9
To get the equation of the line, you need two points that belong to this line.
From the given graph, we can choose any two points: (0,-4) and (-2,0)
The general for of the linear straight line is:
y = mx + c where m is the slope and c is the y-intercept
First, we will calculate the slope using the following rule:
slope = (y2-y1) / (x2-x1)
slope (m) = (0--4) / (-2-0) = 4/-2 = -2
The equation of the line now is: y = -2x + c
Then, we will get the value of the c. To do so, we will choose any point and substitute in the equation. I will choose the point (0,-4)
y = -2x + c
-4 = -2(0) + c
c = -4
Based on the above calculations, the equation of the line is:
y = -2x - 4
6 divided by 1/4 = 24 + 12 divided by 1/4 = 48, then 48 + 24 = 72