Question

Solve the equation with substitution method for the following equation 2x+ y = 7 ; 4x- 3y = 1

Answer 1

$\Large{\underline{\textbf{Question:}}}$

Solve the equation with substitution method for the following equation 2x+ y = 7 ; 4x- 3y = 1

$\Large{\underline{\textbf{Answer:}}}$

2x+ y = 7 ...(i)

4x- 3y = 1 ...(ii)

First we will take (i) equation...

$\rightarrow$ 2x + y = 7

$\implies$ 2x = 7 - y

$\implies$ x = $\frac{7-y}{2}$ .....(iii)

Put the value of equation (iii) in equation (ii)

$\implies$ $4( \frac{7 - y}{2} ) - 3y = 1 \\ \frac{21 - 4y}{2} - 3y = 1 \\ \frac{21 - 4y - 6y}{2} = \\ \frac{21 - 10y}{2} = 1 \\ 21 - 10y = 2 \\ 10y = 21 - 2 \\ y = \frac{19}{10}$

Put the value of y in equation (iii)

$x = \frac{7 - \frac{19}{10} }{2} \\ \\ x = \frac{ \frac{70 - 19}{10} }{2} \\ x = \frac{ \frac{51}{10} }{2} \\ x = \frac{51}{20}$

So, x = 51/20 and y = 19/10