Chapter 6 - Algebra: Equations and Inequalities - Chapter 6 Test - Page 405: 3

\[x=-\frac{64}{5}\].

Consider the equation\[12x+43=7x-21\]. Subtract \[7x\]from both sides to get, \[5x+43=-21\] Subtract 43 from both sides to get, \[5x=-64\] Divide both sides by 5 to get, \[x=-\frac{64}{5}\] Hence, the solution of the given equation is\[x=-\frac{64}{5}\].