Question

Solve the system x - y = 3 and 3x - 8y = 9. What is the value of y?
A. 3
B. 0
C. 6
D. -2

Answer 1

\(\Large \color{MidnightBlue}{\Rightarrow -y = 3 - x }\)
\(\Large \color{MidnightBlue}{\Rightarrow y = -3 + x }\)

Get it till now?

\(\Large \color{MidnightBlue}{\Rightarrow x - (-3x + x) = 3 }\)
\(\Large \color{MidnightBlue}{\Rightarrow x + 3x - x = 3 }\)
\(\Large \color{MidnightBlue}{\Rightarrow 3x = 3 }\)
\(\Large \color{MidnightBlue}{\Rightarrow x = 1 }\)

Now,

\(\Large \color{MidnightBlue}{\Rightarrow 1 - y = 3 }\)
\(\Large \color{MidnightBlue}{\Rightarrow -y = 2 }\)
\(\Large \color{MidnightBlue}{\Rightarrow y = -2 }\)

Answer 2

Great