Answer:
0.034921 miles or 1843774 feet tall
Step-by-step explanation:
Using trigonometric functions we know that 
and 
where 
=angle and r is the hypotenuse of the triangle.
First we will calculate the hypotenuse using the x equation, since we know x = 1 mile (distance from the building on the ground) we have:
Now we will calculate the height of the building using the y equation and so:
The building is 0.034921 miles or approximately 184.3774 feet tall.
Using the points (0,14) and (10,0), the gradient of the line is (14-0)/(0-5) which simplifies to -7/5.
From these points, we can also see that when the x value is zero, the y value is 14. Therefore the y-intercept is 14.
We can then put this into the equation of a straight line, y=mx+c:
y = (-7/5)x + 14
I:2x – y + z = 7
II:x + 2y – 5z = -1
III:x – y = 6
you can first use III and substitute x or y to eliminate it in I and II (in this case x):
III: x=6+y
-> substitute x in I and II:
I': 2*(6+y)-y+z=7
12+2y-y+z=7
y+z=-5
II':(6+y)+2y-5z=-1
3y+6-5z=-1
3y-5z=-7
then you can subtract II' from 3*I' to eliminate y:
3*I'=3y+3z=-15
3*I'-II':
3y+3z-(3y-5z)=-15-(-7)
8z=-8
z=-1
insert z in II' to calculate y:
3y-5z=-7
3y+5=-7
3y=-12
y=-4
insert y into III to calculate x:
x-(-4)=6
x+4=6
x=2
so the solution is
x=2
y=-4
z=-1
-1 / 7 = x
You need to combine the 2x and 5x then devise the 7x from -1
