Question

How to solve 2x-y=1 & 5x+4y=1 by substitution Method

Answer 1

10x-5y=5. multiply by 5

10x+8y=4. multiply by 2

subtract both

y = 1/13

x= 1/2

Answer 2

Step-by-step explanation:

$\sf2x - y = 1\\\implies y = 2x-1$

$\sf5x+4y=1\\5x+4(2x-1)=1\\5x+8x-4=1\\13x=5\\x=\frac{5}{13}$

$\sf y=2x-1\\y=2\times\frac{5}{13} -1\\y=\frac{10-13}{13} \\y=\frac{-3}{13}$