Answer:
this too difficult for my brain i don't like school
Step-by-step explanation:
Answer:
7x+4
Step-by-step explanation:
Distribute:
=(3)(4x)+(3)(−2)+−5x+10
=12x+−6+−5x+10
Combine Like Terms:
=12x+−6+−5x+10
=(12x+−5x)+(−6+10)
=7x+4
Answer:
what does it mean??? I'm confused on what it means or what it's asking
Speed, S = Distance (d) / Time (t) => S= d/t => t= d/S
Let the speed of boat in still water be x mph
Resulting speed upstream = x-4 mph for a distance of 30 miles
Resulting speed downstream = x-4 mph for a distance of 50 miles
Time taken in both distances is equal.
Therefore,
30/(x-4) = 50/(x+4) => 30(x+4) = 50(x-4) => 30x+120 = 50x-200 => 120+200 = (50-30)x => 20x = 320 => x=320/20 = 16 mph
The speed of boat in still water is 16 mph.