Answer:
I think the answer is A
Step-by-step explanation:
Let x be rate of boat in still water
let y be rate of current
we use this equation to relate quantities:
distance = speed · time
we have two unknowns so we might need to create a system of equationss
upstream:
speed (in km/h) = x - y
(we get speed of boat then subtract the current's speed from it since current is going against boat direction)
time = 3 hours
distance = 144 km
downstream:
speed (in hm/h) = x + y
(we get speed of boat then add the current's spd from it since current is going against boat direction)
time = 2 hours
distance = 144 km (same distance upstream and downstream)
using distance = speed times time
for upstream
144 = 3(x-y)
144 = 3x - 3y
for downstream
144 = 2(x+y)
72 = x + y
system of eqns:
144 = 3x - 3y
72 = x + y
solve by substitution: move 72 = x + y into x = 72 - y and subst into other equation for x
144 = 3(72 - y) - 3y
144 = 216 - 3y - 3y
144 = 216 - 6y
144 - 216 = -6y
-72 = -6y
y = 12 km/h
Use x = 72 - y to find x with y = 12: x = 72 - 12 = 60 km/h
rate of boat in still water is 60 km/h
rate of the current is 12 km/h
The answer should be 23+p but im not 100% sure
Answer:
A=400, L=2W, L*W=A so, L*W=400, so, 400=2W*W or 200=W*W or 200=
, 
= W, L=2() and W=, W=14.14 and L=28.28
Step-by-step explanation:
7 + 4x - 10x + 15 = 22 - 6x
You just need to sum terms of polynomial with the same stage of x and not to mix them out. Note that terms without x are actually terms with x^0 because x^0 = 1
Therefore we sum 7 and 15 = 22 and
we sum 4x and -10x = -6x
Answer is B)
