Respuesta :
Answer: The correct option is (D) (5, -2).
Step-by-step explanation: We are given to use the method of substitution to solve the following system of equations :
[tex]3x+7y=1~~~~~~~~~~~~~~~~~~~~~~~~~(i)\\\\y=x-7~~~~~~~~~~~~~~~~~~~~~~~~~~~~(ii)[/tex]
Substituting the value of y from equation (ii) in equation (i), we get
[tex]3x+7y=1\\\\\Rightarrow 3x+7(x-7)=1\\\\\Rightarrow 3x+7x-49=1\\\\\Rightarrow 10x=50\\\\\Rightarrow x=\dfrac{50}{10}\\\\\Rightarrow x=5,[/tex]
and from equation (ii) again, we get
[tex]y=x-7=5-7=-2.[/tex]
Thus, the required solution is (x, y) = (5, -2).
Option (D) is CORRECT.