Answer:
General equation of line : 
--1
Where m is the slope or unit rate
Table 1)
p d
1 3
2 6
4 12
d = Number of dollars (i.e.y axis)
p = number of pound(i.e. x axis)
First find the slope
First calculate the slope of given points
---A
Substitute values in A
Thus the unit rate is 3 dollars per pound.
So, It matches the box 1 (Refer the attached figure)
Equation 1 : 
Since p is the x coordinate and d is the y coordinate
On Comparing with 1
Thus the unit rate is 
dollars per pound
So, It matches the box 2 (Refer the attached figure)
Equation 2 : 
Since p is the x coordinate and d is the y coordinate
On Comparing with 1
Thus the unit rate is 9 dollars per pound
So, It matches the box 3 (Refer the attached figure)
Table 2)
p d
1/9 1
1 9
2 18
d = Number of dollars (i.e.y axis)
p = number of pound(i.e. x axis)
Substitute values in A
Thus the unit rate is 9 dollars per pound
So, It matches the box 3 (Refer the attached figure)
1)
I:x-y=-7
II:x+y=7
add both equations together to eliminate y:
x-y+(x+y)=-7+7
2x=0
x=0
insert x=0 into II:
0+y=7
y=7
the solution is (0,7)
2)
I: 3x+y=4
II: 2x+y=5
add I+(-1*II) together to eliminate y:
3x+y+(-2x-y)=4+(-5)
x=-1
insert x=-1 into I:
3*-1+y=4
y=7
the solution is (-1,7)
3)
I: 2e-3f=-9
II: e+3f=18
add both equations together to eliminate f:
2e-3f+(e+3f)=-9+18
3e=9
e=3
insert e=3 into I:
2*3-3f=-9
-3f=-9-6
-3f=-15
3f=15
f=5
the solution is (3,5)
4)
I: 3d-e=7
II: d+e=5
add both equations together to eliminate e:
3d-e+(d+e)=7+5
4d=12
d=3
insert d=3 into II:
3+e=5
e=2
the solution is (3,2)
5)
I: 8x+y=14
II: 3x+y=4
add I+(-1*II) together to eliminate y
8x+y+(-3x-y)=14-4
5x=10
x=2
insert x=2 into II:
3*2+y=4
y=4-6
y=-2
the solution is (2,-2)
Just square the top and bottom. z^2 over 25
Answer:
<QRS= (10.x - 1) = (10.6 - 1) = 59°
Step-by-step explanation:
the triangle is not accurate but drawing one is truly useful in calculating. Besides, I don't know how it is called in English but it is something about the exterior angles (maybe)
