What is the solution to the following system?

The correct answer is option 3. (20, 4, 5)

Step-by-step explanation:

To solve this problem we use the substitution method.

(i)

(ii)

(iii)  

We start by clearing x in (iii) and clearing y in (ii).

(iii)

(ii)

Now we substitute (iii) in (ii)

(iv)

Now we substitute (iii) and (iv) into (i) and clear z.

(v)

If (v)

We substitute (v) in (iii) and then substitute (v) in (iv)

The correct answer is option 3.

whatvare the choices

step-by-step explanation:

answer: 12   they all have at least 28 days

step-by-step explanation: haha