How do I use elimination to find the solution of the system of equations $3 x + 4 y = 10$ $3x+4y=10$ and $x - y = 1$ $x−y=1$ ?

Question

2929 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-04-22T13:59:40

$x = 2, y = 1$ $x=2, y=1$

$3 x + 4 y = 10 - - (1)$ $3x+4y=10--(1)$

$x - y = 1 - - - (2)$ $x-y=1---(2)$

$(2) \times 4$ $(2)xx4$

$4 x - 4 y = 4 - - - (2 a)$ $4x-4y=4---(2a)$

$3 x + 4 y = 10 - - - (1)$ $3x+4y=10---(1)$

$(2 a) + (1)$ $(2a)+(1)$

$7 x = 14 \Rightarrow x = 2$ $7x=14=>x=2$

subs into $(2)$ $(2)$

2-y=1#

$:.y=1$

quick mental check in $(1)$ confirms trhe solns

How do I use elimination to find the solution of the system of equations 3x+4y=103x+4y=103x+4y=10 and x−y=1x−y=1x−y=1?