Question

solve the following pair of linear simultaneous equations by the method of substitution : 2x +3y-7= 0 , 3x+2y-8 =0​

Answer 1

Answer:

$y=-5\\x=11$

Step-by-step explanation:

2x+3y=7---------------(i)

3x+2y=8---------------(ii)

now by taking (i)

2x+3y=7

2x=7-3y

$x=\frac{7-3y}{2}$---------------(iii)

by substituting (iii) in (ii)

$3(\frac{7-y}{2})+2y=8$

$\frac{21-3y}{2} +2y=8$

$\frac{21-3y}{2} +\frac{4y}{2}=8$

$\frac{21-3y+4y}{2}=8$

$\frac{21+y}{2} =8$

$21+y=8(2)$

$21+y=16$

$y=16-21$

$y=-5$   ---------------(iv)

substituting (iv) in (i)

$2x+3(-5)=7$

$2x-15=7$

$2x=7+15$

$2x=22$

$x=\frac{22}{2}$

$x=11$  -----------------(v)

equation (iv) and (v) are the answers

$y=-5\\x=11$