Given at you have an equilateral triangle, all sides have the same length.
Therefore,
First side 2x-7 = Second side x+y-9 = Third side y+5
Let us look at the second and third sides for now:
x+y-9 = y+5
x = y+5 - (y-9)
x = y-y+5+9
x = 14
Then we look at equating the first and third sides:
2x-7 = y+5
y = 2x-7-5
Substitute x =14 in the equation above:
y = 2(14)-7-5
= 28-7-5
= 21-5
= 16
The length of the third side is:
y+5 = 16 +5 = 21
Given that the length of each sides are the same in an equilateral triangle, all sides have the length 21cm.
Substitute 136.5 for y.




Compare this equation with 
a = 1, b = - 191, c = 8190
or
or

or

or

or

or

x = 126 or x = 65
Hence, the points on the curve are (65, 136.5) and (126, 136.5).
The width of the air space is the distance between these points.
Width = 
= 
= 126 - 65
= 61
Hence, width of the air space is 61m.
Answer:
f(x) = -4x + 19
Step-by-step explanation:
I used a calculator, pls let me know if im incorrect
Answer:
b
Step-by-step explanation:
x=2
Answer: Congruent angles are angles that have the same measure. ... y = 67 x = 180 – 67 = 113. 2. x = ______ y = ______. 3x – 5 = 127. +5 +5. 3x = 132 ... Find the measure of the angle and give the reason for knowing it. ... Solve for the unknown values: ... 2) AD. 3) AB. 4) BC. 24. In ΔABC, If CA ≅ CB and m∠A = 50, find the m∠B.