Answer:
see below
Step-by-step explanation:
The slopes of parallel lines are the same. The slopes of perpendicular lines are negative reciprocals of each other, hence their product is -1.
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For the most part, the concept of adding slopes of lines does not relate to parallel or perpendicular lines in any way.
Answer:
4x-10
Step-by-step explanation:
Multiply both by 2, 2x times 2 is 4x, and 5 times 2 is 10, so it becomes 4x-10.
Let's define variables:
s = original speed
s + 12 = faster speed
The time for the half of the route is:
60 / s
The time for the second half of the route is:
60 / (s + 12)
The equation for the time of the trip is:
60 / s + 60 / (s + 12) + 1/6 = 120 / s
Where,
1/6: held up for 10 minutes (in hours).
Rewriting the equation we have:
6s (60) + s (s + 12) = 60 * 6 (s + 12)
360s + s ^ 2 + 12s = 360s + 4320
s ^ 2 + 12s = 4320
s ^ 2 + 12s - 4320 = 0
We factor the equation:
(s + 72) (s-60) = 0
We take the positive root so that the problem makes physical sense.
s = 60 Km / h
Answer:
The original speed of the train before it was held up is:
s = 60 Km / h
Answer: 9+4n-1 = 20
We can solve this by substitution.
Replace n with the value given, 3 (remember 4n means 4 times n):
9 + 4*3 - 1
Then work it out using arithmetic
9+12-1
=20
Answer:
-4z
Step-by-step explanation:
