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
Answer:
10 is the answer
Step-by-step explanation:
Beacause 2 * 5 =10
and 5*2=10
From the equation y = 4x, each strawberry contains 4 calories.
<h3>What is an
equation?</h3>
An equation is an expression that shows the relationship between two or more numbers and variables.
Let y represent the number of calories in x strawberries. Hence:
y - 0 = [(27 - 0)/(6.8 - 0)](x - 0)
y = 4x
From the equation y = 4x, each strawberry contains 4 calories.
Find out more on equation at: brainly.com/question/2972832
#SPJ1
1. a = 1/2x - 3
2. a = 2x + 7
1iii
2b
3a
4e
Hope it helps pls add brainlist if you want your answers to be correct or...... not.... ;)
