Question

9x-10y=-12
2x+3y=13
substituting method​

Answer 1

Answer:

9x-10y =-12

2x+3y. =. 13

9x-10y =-12

9x=-12+10y

x=-12+10y/9

2x+3y=13

2(-12+10y/9)+3y=13

-24+20y/9 +3y =13

(-24+20y×1 +3y×9)/9=13

(-24+20y+27y)/9=13

(-24+47y)/9=13

-24+47y=117

47y=117+24

47y=141

y=141/47

y=3

9x-10y=-12

9x-10×3= -12

9x- 30= -12

9x= -12+30

9x= 18

x= 18/9

x=2

checking:

9x-10y= -12

9×2-10×3

18-30

= -12