Question

Solve $3x+4y=10$ and $2x-2y=2$ by substitution method.

Answer 1

By substitution method,

$3x+4y=10$ & $2x-2y=2\Rightarrow 2(x-y)=2\Rightarrow x-y=1$ ___ (2)

$\therefore x=y+1\to \left(1\right)$.

Substituting in equation (2).

$\therefore 3x+4y=10\Rightarrow 3(y+1)+4y=10$

$\Rightarrow 3y+3+4y=10\Rightarrow 7y=7\Rightarrow y=1$

$\therefore x=1+1=2$

$\therefore x=2,y=1$