A. x + 5=12
7x = 21
B. b - 2/3 = 5/6
1/5m = 20
C. 45 = 3(x + 1)
D. 22.5 = 1.5x
E. Mark has $20 in his bank account. He saves $5 each week. How much money does Mark have in his account after 9 weeks? Use w to represent the number of weeks and t to represent the total amount Mark has after any number of weeks.
Answer:

Step-by-step explanation:
In order to solve this it is always a good idea to start by drawing a diagram of the situation (See attached picture).
From the diagram we can see that we are dealing with similar triangles. We can use similar triangles to build an equation that relates the length of the shadow with the height of the lamp, so we get:

the height of the lamp can be found by subtracting the
distance the lamp falls in a given time t from the original 30ft the lamp was located at.
So the equation will now lok like this:

So now we can solve the equation for L, we can start by multiplying by the LCD SO WE GET:

next, we can distribute the right side of the equation so we get:

and subtract 6L from both sides so we get:

and factor L, so we get:

and solve for L:

now, we can differentiate this equation by using the chain rule, so we get:

which can be simplified to:

and now we can substitute t for 1s so we get:


They all look pretty good to me, you should be fine boo xxo
Answer:
The area is 10
Step-by-step explanation:
The blue area can be divided into a square and a number of triangles, but it is just as easy to subtract the areas of the triangles around the outside:
The blue area is ...
16 -1 -1 -1 -2 -1 = 10 . . . . . . (CCW from upper left)
Also you can count the number of dots between each curve