The slope-intercept form of a line:

We have:

Substitute:


Put the values of coordinates of the point (1, 5) to the equation of a line:

Answer: 
2+1.25f=10-2.75f Add the variables
2+4f=10 isolate the variable
4f=8
f=2
Answer:
68.17m
Step-by-step explanation:
Please see attached a rough sketch of the scenario
Step one:
Given data
Height of victim= 4.5ft
The horizontal distance of the snipper from the building = 780ft
The angle of elevation= 5 degrees
Required
The vertical distance
The opposite= the vertical distance
789 ft = the adjacent
Step two:
Applying SOH CAH TOA
tan ∅= opp/adj
tan 5= opp/780
cross multiply we have
0.0874= opp/780
cross multiply we have
0.0874*780= opp
opp= 68.17m
The sniper shoots from a vertical distance of 68.17m
Answer:
23) x= 3, y = 4
24) Any (x,y) values where x = 1.5 - 2y
Step-by-step explanation:
For the first system(23), it goes like this
[1 2 | 7]
[2 1 | 8]
We need to do L2 = L2 - 2L1, so now it is
[1 2 | 7]
[0 -3 |-6]
So, now we have:
-3y = -6 *(-1)
3y = 6
y = 2
x + 2y = 7
x + 4 = 7
x = 3
Now for system 24, we have:
[-1 2 | 1.5]
[2 -4| 3]
We do L2 = L2 + 2L1, so we have:
[-1 2 | 1.5]
[0 0| 0]
So there are infinite solutions for this system. The solution for this system will be each (x,y) pair where x = 1.5 - 2y.