Question

Solve the following simultaneous equations by the method of equating coefficients.$3x-4y=7;5x+2y=3$ .

• A. $x=1,y=-1$
• B. $x=2,y=1$
• C. $x=5,y=2$
• D. $x=4,y=-3$

Answer 1

The correct option is A $x=1,y=-1$

$3x-4y=7$ ...(i)
$5x+2y=3$ ...(ii)
On multiplying (i) by 5 and (ii) by 3, we get
$15x-20y=35$
$\underset{–}{\underset{-}{1}5x\underset{-}{+}6y=\underset{-}{9}}$
$-26y=26$
$\therefore y=-1$
On putting $y=-1$ in (i), we get
$3x-4(-1)=7$
$x=1$
$\therefore x=1,y=-1$