<u>Hello:</u>
<u />
<u>Okay, this problem should be taken in a series of steps</u>:
<u>What is the slope's formula?</u>

- (x₁,y₁) -- first point
- (x₂,y₂) -- second point
<u>Okay, now let's use this knowledge</u>
10. (5,-19) and (-5,21)

11. (12,1) and (12, -1)

12. (8,7) and (4,7)

<u>Answer:</u>
- Question 10: -4
- Question 11: undefined
- Question 12: 0
Hopefully that helps!
Answer:
x = 2.56, y = -2.63
Step-by-step explanation:
I first multiplied the second equation by two, getting
4x-6y = 26
I then subtracted the equations
4x+2y = 5
- 4x-6y = 26
--------------------
8y = -21
y = -2.63
with y solved, I plugged it into the second equation to get x:
2x-3(-2.63) = 13
2x+ 7.89 = 13
2x = 5.11
x = 2.56
I hope this helped! ;D