Question

the solution is n = -2 verified as a solution to the equation 1.4n + 2 = 2n + 3.2. what is the last line of the justification?
○ 0.8 = 0.8
○ -0.8 = -0.8
○ 3 = 3
○ -3 = -3

Explanation:

Step1: Substitute \( n = -2 \) into the equation

Substitute \( n = -2 \) into \( 1.4n + 2 \) and \( 2n + 3.2 \) respectively.
For the left - hand side (LHS): \( 1.4\times(-2)+2=-2.8 + 2=-0.8 \)
For the right - hand side (RHS): \( 2\times(-2)+3.2=-4 + 3.2=-0.8 \)

Step2: Check the equality

After substitution, we get \( - 0.8=-0.8 \), which shows that \( n = - 2 \) is a solution of the equation.

Answer:

B. \(-0.8 = -0.8\)