Answer:
<h2>
76 cm</h2>
Step-by-step explanation:

1; 127 mi
2;78
Sorry i did not know the other answers
I hoped this helped
Mid point of x:
{2-(-6)} : 2
8 : 2
4
mid point of y:
(5-3) : 2
2 : 2
1
so (4,1)
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)
54, 36, 24 are the 1st 3 element of a geometric progression with 2/3 as a common ratio: PROOF:
the 1st term is 54, (a₁= 54) the 2nd term a₂ = 24, then
(a₂ = a₁.r) or 36 = 54.r → r= 36/54 = 2/3. Same logique for the 3rd term.
So 2/3 is common ratio. We know that :U(n) = a.(r)ⁿ⁻¹. Then if a =54 and r = x (given by the problem), then f(x) = 54.xⁿ⁻¹
n, being the rank of any element of this geometric progression