9514 1404 393
Answer:
350 km/h
Step-by-step explanation:
Speed = distance/time
speed = (700 km)/(2 h) = 350 km/h
Answer:
2x+17
Step-by-step explanation:
-4y+8-3x+4y+9+5x
Combine like terms
-3x +5x -4y +4y +8+9
2x +0 +17
Let's start from what we know.
Note that:
(sign of last term will be + when n is even and - when n is odd).
Sum is finite so we can split it into two sums, first
with only positive trems (squares of even numbers) and second
with negative (squares of odd numbers). So:
And now the proof.
1) n is even.
In this case, both
and
have
terms. For example if n=8 then:
Generally, there will be:
Now, calculate our sum:
So in this case we prove, that:
2) n is odd.
Here,
has more terms than
. For example if n=7 then:
So there is
terms in
,
terms in
and:
Now, we can calculate our sum:
We consider all possible n so we prove that:
Answer:
x =1, x = 0 is extraneous.
Step-by-step explanation:
5/x = 4x + 1 / x^2
5x^2 = 4x^2 + x
5x^2 - 4x^2 - x = 0
x^2 - x = 0
x(x - 1) = 0
x = 0, 1.
x is not a solution because 5/x is undefined.