Answer:
Option 2 50 ≤ s ≤ 100
Option 5 She could deposit $50
Option 6 She could deposit $75
Step-by-step explanation:
Let
s -----> amount of money Layla deposit into a saving account
we know that
25%=25/100=0.25
50%=50/100=0.50
so
-----> 
-----> 
The compound inequality is

<em>Verify each case</em>
case 1) 25 ≤ s ≤ 50
The statement is false
see the procedure
case 2) 50 ≤ s ≤ 100
<u>The statement is True</u>
see the procedure
case 3) s ≤ 25 or s ≥ 50
The statement is false
Because is s ≤ 100 and s ≥ 50
case 4) s ≤ 50 or s ≥ 100
The statement is false
Because is s ≤ 100 and s ≥ 50
case 5) She could deposit $50
<u>The statement is true</u>
Because the value of s satisfy the compound inequality 
case 6) She could deposit $75
<u>The statement is true</u>
Because the value of s satisfy the compound inequality 
Using the quadratic formula, we have:

, so our solutions are

and

.
This would be easy if you made more sense out of the question.
Answer:
23.6666666667
Step-by-step explanation:
Let's call the younger student's age A and the older student's age B. The teacher's age will be T.
B = 2A
T = 5B
T+5 = 5(A+5)
Simplify the last equation.
T+5 = 5A+25
T = 5A+20
Now we have two equations solved for T, so we can set them equal to each other.
5B = 5A + 20
We can plug 2A in for B
5(2A) = 5A + 20
10A = 5A + 20
5A = 20
A = 4
To find T, we plug 4 in for A in T = 5A + 20
T = 5(4) + 20
T = 40
The answer is 40 years old.