Answer attached, but more letters needed
Answer:

x = 10 months
Step-by-step explanation:
Given:
Initial deposit = $100
Weakly deposit = $15
Solution:
We need to create an equation where total amount is y is equal to initial deposit plus multiplication of weakly deposit and month x, so the equation is written as.
---------(1)
Where:
Y = Total amount
x = Number of months.
Second thing we need to find the month for y = $250
Now, we substitute y = 250 in equation 1.




x = 10 months
Therefore, we need to required 10 months for $250.
Answer:
b = 1
Step-by-step explanation:
Given the equation is:
- 5b + 2b - (-b) + 7 = 5
We separate the terms of b and the constants. To do that we subtract 7 from both the sides. We get:
- 5b + 2b - (-b) + 7 - 7 = 5 - 7
⇒ - 5b + 2b - (-b) = - 2
Now, simplifying the terms with 'b'.
⇒ -5b + 2b + b = - 2
⇒ (-5 + 2 + 1)b = - 2
⇒ -2b = -2
Dividing both the sides by -2, we get:
b = 1 which is the required answer.
Store one since the 15% is take off 90 dollars which makes it 510