Question

Solve the equation by substitution method $2x+3y=9$ , $3x+4y=5$

Answer 1

We have,

$2x+3y=9$ ……. (1)

$3x+4y=5$ …… (2)

Now,

$y=\frac{9-2x}{3}$

On putting the value of $y$, in equation (2), we get

$3x+4\left(\frac{9-2x}{3}\right)=5$

$3x+\frac{36-8x}{3}=5$

$9x+36-8x=15$

$x=15-36$

Now, put the value of $x$ in equation (1), we get

$y=\frac{9-2(-21)}{3}$

$y=\frac{9+42}{3}$

$y=\frac{51}{3}=17$

Hence, this is the answer.