Let <em>a</em> denote the airplane's speed in still air, and <em>w</em> the windspeed.
When the plane flies against the wind, it can travel an average speed of
(4500 km) / (6 h) = 750 km/h
so that
<em>a</em> - <em>w</em> = 750 km/h
Flying with the wind, it moves at a speed of
(2910 km) / (3 h) = 970 km/h
so that
<em>a</em> + <em>w</em> = 970 km/h
Add the two equations to eliminate <em>w</em> and solve for <em>a</em> :
(<em>a</em> - <em>w</em>) + (<em>a</em> + <em>w</em>) = 750 km/h + 970 km/h
2<em>a</em> = 1720 km/h
<em>a</em> = 860 km/h
Subtract them to eliminate <em>a</em> and solve for <em>w</em> :
(<em>a</em> - <em>w</em>) - (<em>a</em> + <em>w</em>) = 750 km/h - 970 km/h
-2<em>w</em> = -220 km/h
<em>w</em> = 110 km/h
A is correct.
Work shown:
M- 6 packages delivered
T- 6+4=10
W- 6+6=12
Now add packages delivered each day
6+10+12=28
Please vote my answer brainliest. thanks!
Answer:
(x + 4)(x - 4)
Step-by-step explanation:
There are actually quite a lot of pairs of binomials the disproves Eric's conclusion, but they all model after the same special product: a^2 - b^2.
The special product a^2 - b^2 can be factored into (a + b)(a - b) and for all real a and b, it will come out as a binomial.
Here is an example:
(x + 4)(x - 4)
We can use the distributive property to get:
x^2 - 4x + 4x - 16
which is the same as
x^2 - 16
This would disprove Eric's conclusion.
The answer is x=6, have a good day!
Answer:
can u show me a pic of the question so it is easier
