Question 6 • CMS 2026-2027 NC Math 1 CREDIT RECOVERY
The equations negative A minus 7 b is equal to 14 and negative 4 A minus 14 b is equal to 28 represent a system of linear equations. Which statement correctly explains how to eliminate the variable b when solving the system of equations?
Answer
A
Multiply the first equation by 2 and add it to the second equation. Then solve the resulting equation, negative 2 A is equal to 0 .
B
Divide the second equation by 4 and add it to the first equation.
C
Multiply the first equation by negative 2 and add it to the second equation. Then solve the resulting equation, negative 2 A is equal to 0 .
D
Divide the second equation by negative 4 and add it to the first equation.
Explanation
The b-terms are −7b in the first equation and −14b in the second. Multiplying the first equation by −2 changes it to 2A + 14b = −28; adding the second equation cancels the b-terms and gives −2A = 0. Therefore, the correct statement is to multiply the first equation by −2 and add it to the second.
AI-written and checked against the verified answer.