Question

2. Solve the linear pair of equations x + y =5 and
2x - 3y = 4.​

Answer 1

By elimination method,x=19/5 and y=6/5

by substitution method,x=19/5 and y=6/5

Step-by-step explanation:

By elimination method

$\begin{gathered}x+y=5\times3-(i)\\2x-3y=4\times1-(ii)\end{gathered}$

After solving equation (i) and (ii) we get,

$\begin{gathered}5x=19\\x=\frac{19}{5}\end{gathered}$

$Put x=\frac{19}{5}$

in equation (i)

$\begin{gathered}x+y=5\\\frac{19}{5}+y=5\\y=5-\frac{19}{5}\\y=\frac{25-19}{5}\\y=\frac{6}{5}\end{gathered}$

By substitution method

$\begin{gathered}x+y=5-(i)\\2x-3y=4-(ii)\\\end{gathered}$

x = 5-y from equation (i)

Put x = 5y in equation (ii)

$\begin{gathered}2(5-y)-3y=4\\1-2y-3y=4\\10-5y=4\\-5y=4-10\\y=\frac{6}{5}\end{gathered}$

Put y =$\frac{6}{5}$

in equation (i)

$\begin{gathered}x=5-\frac{6}{5}\\x=\frac{19}{5}\end{gathered}$