Maria solved the equation below and got x = –4. Which of the following choices verifies that her solution is correct?

5x + 22 = x + 6

A.
5(–4) + 22 = (–4) + 6
–20 + 22 = –2
–2 = –2

B.
5(–31) + 22 = (–10) + 6
–26 + 22 = –4
–4 = –4

C.
5(–4) + 22 = (–4) + 6
5(18) = (–4) +6
24 = 24

D.
5(–4) + 22 = (–4) + 6
–20 + 22 = 2
2 = 2

Question

Maria solved the equation below and got x = –4.  Which of the following choices verifies that her solution is correct?
 
5x + 22 = x + 6
  
A.
5(–4) + 22 = (–4) + 6
   –20 + 22 = –2
              –2 = –2         
 
B.
5(–31) + 22 = (–10) + 6
    –26 + 22 = –4
              –4 = –4     
 
C.
5(–4) + 22 = (–4) + 6
         5(18) = (–4) +6
              24 = 24 
 
D.
5(–4) + 22 = (–4) + 6
   –20 + 22 = 2
               2 = 2

mhchen · Answer

(A) is NOT correct because (-4)+6 = 2
(B) is NOT correct because 'x' is NOT SUBSTITUTED WITH -4
(C) is NOT correct because the 2nd step of both sides literally make no sense at all.
(D) I didn't find any errors in (D), all steps are vaild.