Answer:

Step-by-step explanation:
The given Equation is
.................(i)
Adding (
) on both sides of (i)
solving and cancelling out the terms will give
⇒
⇒
...................(ii)
Now we Know that
Applying this on equation (ii)

This will lead us to
Either 2x-3 =0 .......(iii) or 2x+3=0 ..........(iv)
Solving equation (iii) for value of x
2x - 3 =0
adding 3 on both sides
2x -3 +3 = 0+ 3
2x = 3
Cross multiplying gives

Solving equation (iv) for value of x
2x + 3 =0
adding -3 on both sides
2x -3 +3 = 0- 3
2x = -3
Cross multiplying gives

so
and 
B......……...................
First, we need to convert all the fractions to have the same denominator. 10 and 25 are both multiples of 100, so 100 would be appropriate.
Sam has a 7/25 chance. Because we want ?/100, something needs to change. To get from 25 to 100, you need to times 25 by 4, right? So, do the same with the 7.
7 x 4 = 28. Therefore Sam has a 28/100 chance.
Sue has 3/10. Using the same method, we can see that 3 needs to be multiplied by 10 (because 10 times 10 = 100). So Sue has a 30/100 chance.
Tom is already in the fraction we like, so just keep this as 21/100.
Now, add 28/100, 30/100 and 21/100 to get 79/100.
Because won of them will get the role of class president, we know that the probability adds to 1. To get a full probability (100/100, or 1), what needs to be added to 79/100?
Another way of going about this is 100/100-79/100. The answer is 21/100
The probability of Liz winning is 21/100.
Let me know if this is still unclear, I would be more than happy to explain in more detail if necessary :)
(5,-3), (-7,9) are two possible point coordinates
Answer:
The average velocity the entire trip was 43.25 mi/h
Step-by-step explanation:
In this case we have to calculate an average based on the miles traveled. First we have to calculate the total of miles traveled, then calculate the portion of the total travel of each and with this calculate the average speed during the trip. First the total miles traveled:

Now the percentages:
At 57 mi/h were 
At 44 mi/h were 
At 37.8 mi/h were 
Now multiplying the speed by the portion and summing them we can have the average velocity:

The average velocity the entire trip was 43.25 mi/h