4 cups per quarter
4 x 7 = 28
28 kids can have a cup of hot chocolate.
Distribute:
3x-12=12
Add 12 over
3x=24
divide by 3
x=8
Let's use the furthest left point on the triangle to figure out the translation.
Blue triangle = (-5,1)
Black triangle = (-3,-1)
To get from -5 to -3 we moved the triangle 2 units to the right, which means that we added 2.
To get from 1 to -1, we moved the triangle 2 units down, which means we subtracted 2.
Rule: {2, -2}
Hope this helps!
Let the speed of the boat be x
so going against the current the speed is x-7
going with the current the speed is x+7
let the distance be d
time = distance / speed
time to go against the current = d/(x-7)
time to go with the current = d/(x+7)
time going against the current is 3 times going <span>with the current
</span>
d/(x-7) = 3d/(x+7)
⇒⇒⇒ divide by d
1/(x-7)
= 3/(x+7)
x+7
= 3(x-7)
x+7 = 3x - 21
2x = 28
x = 14
So, the speed of the boat in still water is = 14 mph