PL HELP URGENTLY!Explain the Error Find the error in the solution, and then solve it correctly.

7x + 21 + 9x = 2

7x + 21 = -7

7x = -28

-28

X =

7

(select) was subtracted from the left side, but (select) was subtracted from the

right side. The Subtraction Property of Equality states that you can subtract the

same number from each side and the equation will remain true. But 9x and 9 are

not the same number (unless x is (select)).

x =