Hi there,
1)
6 + (w - 10) = 5
6 + w - 10 = 5
- 4 + w = 5
w = 5 + 4
Hence, W = 9
2)
2/3 + y - 1/9 = 7/9
5/9 + y = 7/9
y= 7/9 - 5/9
Hence, Y = 2/9
4)
4x - 3/2x - 15/4 = 3/8
32x - 12x - 30 = 3
20x - 30 = 3
20x = 3 + 30
20x = 33
Hence, the answer is 33/20
5)
0.7(3s + 4) - 1.1s = 7.9
2.1s + 2.8 - 1.1 = 7.9
s + 2.8 = 7.9
s = 7.9 - 2.8
Hence, the answer is 5.1
Hope this all helps :)
To find the rate of change, or slope, pick two points. The slope, is change in y coordinates over change in x coordinates.

.
In this case, the slope is

.
Remember that subtracting a negative number equals adding the number without the negative sign.
a-(-b) = a+b
Now for the y-intercept. The y-intercept is where the graph intersects the y-axis, where x = 0.
You have the coordinate (0, -1), where x = 0. So the y-intercept is -1.
Putting these values into the slope-intercept form y = mx+b, the equation is
y = -5x - 1
Well, you could assign a letter to each piece of luggage like so...
A, B, C, D, E, F, G
What you could then do is set it against a table (a configuration table to be precise) with the same letters, and repeat the process again. If the order of these pieces of luggage also has to be taken into account, you'll end up with more configurations.
My answer and workings are below...
35 arrangements without order taken into consideration, because there are 35 ways in which to select 3 objects from the 7 objects.
210 arrangements (35 x 6) when order is taken into consideration.
*There are 6 ways to configure 3 letters.
Alternative way to solve the problem...
Produce Pascal's triangle. If you want to know how many ways in which you can choose 3 objects from 7, select (7 3) in Pascal's triangle which is equal to 35. Now, there are 6 ways in which to configure 3 objects if you are concerned about order.
Answer:
It's not a real solution
Step-by-step explanation:
She worked as a carpenter for 12 hours and as a blacksmith for 18 hours.
Assuming you mean she earned $20 as a carpenter and $25 as a blacksmith per hour, with a total of 30 hours for $690,
let c represent carpenter hours and b for blacksmith hours.
20c + 25b = 690
c + b = 30
Subtract b from each side so that c = 30 - b
Plug this value into the first equation
20(30 - b) + 25b = 690
600 - 20b + 25b = 690
600 + 5b = 690
5b = 90
b = 18
To find c, plug this value of b into the other equation
c + 18 = 30
c = 12