The signs of the numbers in the problem matter because if a number is negative in the equation than you're answer could be negative. ex. -3/9= -3 but if the negative sign wasn't there than the answer would be wrong bc the answer would be positive.
hope thats what you need hope it helps.
Answer:
-2
Step-by-step explanation:
Hope you do well on your assignment!
<h3>
Answer: -10</h3>
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Work Shown:
First we need to evaluate f(3)
f(x) = -x^2 + 2x
f(x) = -(x)^2 + 2(x)
f(3) = -(3)^2 + 2(3) ... replace every x with 3; apply PEMDAS to simplify
f(3) = -9 + 6
f(3) = -3
Then we subtract 7 from both sides
f(3) - 7 = -3 - 7
f(3) - 7 = -10
The rate of each train of the northbound train traveled 10 miles per hour faster than the southbound train 26 miles per hour.
<h3>what is speed?</h3>
Speed is the time rate at which an object is moving along a path
Let the speed of southbound train is x miles/hour
so, northbound train has speed of x+10 miles/hour.
then, Speed of both train = Total distance/ total time
(x+10+x)=210/5
2x+10= 210/5
2x+10= 42
2x= 32
x= 16 miles per hour (southbound train)
northbound train: 16+10=26 miles per hour
Learn more about this concept here:
brainly.com/question/15544987
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