<u><em>Answer:</em></u>
- 84x - 70
<em><u>Step-by-step explanation:</u></em>
We want to combine like terms:
-10 - 90x + 6x - 60
We can see (-10) and (-60) are both regular constants so:
- 10 - 60 = - 70
Then (-90x) and (+ 6x):
6x - 90x = - 84x
- 84x - 70
3 and 4/9 would be the answer to this.
Distance swam in 5 minutes = 85.4 yards
Since, 1 min = 60 seconds and 1 yard = 0.91 meter
5 minutes = 
seconds
85.4 yards = 
meters
So, Distance swam in 300 seconds = 77.7 meters
Now, we will use unitary method to determine the distance swam in 70 seconds.
Distance swam in 1 second = 
= 0.26 meter
So, Distance swam in 70 seconds = 
= 18.2 meters
Therefore, the swimmer took 70 seconds to cover the distance of 18.2 meters.
For polar form you need to find the modulus (length of the vector) and the argument (angle of the vector) and present in form rcis(Arg) or re^Argi
start with the modulus r=sqrt(a^2 +b^2)
=sqrt(-2^2 +2^2)
= sqrt(4+4)
=sqrt(8)
=2sqrt(2)
next the argument, firstly arg=tan(b/a)
= tan(2/2)
=tan(1)
=pi/4 . (exact values table)
Now consider the quadrant the complex number is in, as it is (-2,2) it is in the second quadrant and as such your Arg value is:
Arg=pi-arg
= pi-pi/4
= 3pi/4
add it all together and your complex number in polar form is:
2sqrt2cis(3pi/4)
note: cis is short hand for cos(x)+isin(x), it is possible your tutor would rather you use the complex exponential form which is simply re^Argi and your answer would look like:
2sqrt2e^(3pi/4)i
Also notice the difference between arg and Arg as this often slips students up and always present Arg in prinicple argument form ie -pi<Arg<pi
Hopefully this has been clear enough and good luck
100x - 200 > 50x - 75
100x - 50x > -75 + 200
50x > 125
x > 2,5
Good Luck
