Answer:
This statement is sometimes true
Thanks this came in handy bc I'm a beginner
55mph.
you can solve it using the equation distance=speed x time
your total distance is 714, and you have 2 trains, one traveling some speed, x, and one traveling x+8, both traveling for 7 hours.
your equation would look like this

and you can then solve for x, which would be 47. this is the speed of the slower train, but 47+8=55 with give you the speed of the faster train.
To determine the missing angle you simply subtract the angle you know from 180 because a flat line is 180 degrees. If it is a circle you subtract the number from 360. Hope this helps!
Answer:
x = 0
y = -12
Step-by-step explanation:
Plug in what y is equal to into the second equation
-3(x - 12) = 2x + 36
Distribute the -3
-3x + 36 = 2x + 36
-36 -36
-3x = 2x
They cannot be equal so x = 0
Plug in 0 into the y equation
y = 0 - 12
y = -12