Question

Solve the following pair of linear equations 3x - 5y =4. 2y +7 =9x

Answer 1

$\huge{\mathfrak{\blue{\underline{\underline{Solution:-}}}}}$

$\sf{We\;have,}$

$\sf{3x-5y=4}\\ \\ \sf{3x-5y-4=0\;\;\;\;........(1)}$

$\sf{2y+7=9x} \\ \\ \sf{9x=2y+7\;\;\;.......(2)}$

$\sf{So,\;multiple\;equation\;(1)\;by\;3\;to\;get}$

$\sf{9x-15y-12=0}$

$\sf{Replace\;the\;value\;from\;equation\;(2),}$

$\sf{2y+7-15y-12=0}$

$\sf{13y=-5}$

$\sf{y=-\frac{5}{13}}$

$\sf{Replace\;the\;value\;of\;y\;in\;equation\;(2),\;we\;get}$

$\sf{x=\frac{9}{13}}$

$\sf{So,}$

${\boxed{\boxed{\bf{\red{y=-\frac{5}{13}}}}}}$

${\boxed{\boxed{\bf{\red{x=\frac{9}{13}}}}}}$

Answer 2

X = 9/13

y= -5/13

Step-by-step explanation:

3x - 5y =4. -------(i)

2y + 7=9x

9x - 2y = 7 ---------(ii)

from (i)

3x =4 +5y

X= 4 + 5y/3 ----------(iii)

putting the value of X in (ii)

9(4+5y)/3 -2y =7

3(4 + 5y) - 2y = 7

12 + 15y -2y = 7

12+ 13y = 7

13y = 7- 12

13y = -5

y = -5/13

putting the value of y in (iii)

X = 4 + 5(-5/13) /3

= (4 -25/13) /3

=(52 -25/13) / 3

=(27 /13)(1/3)

= 9/13

hope this helps u....