Question

3x-4y=18
4x - 5y=22
eliminate y by
cofficient method
. please explain me how can I solve it​

Answer 1

3x-4y=18-(i)

4x-5y=22-(ii)

multiply equation (i) by 5 and equation (ii) by 4,

3x-4y=18 4x-5y=22

x5 x4

________ ________

15x-20y=90-(iii) 16x-20y=88-(iv)

subtract equation(iii) and (iv)

15x-20y=90

-16x+20y= -88

____________

-x=2

x= -2

put x=2 in equation(i)

3x-4y=18

3(-2)-4y=18

-6-4y=18

-4y=18+6

-4y=24

-y=24/4

-y=6

y= -6

therefore (x,y)=(-2,-6) is the solution

hope it help you

Answer 2

Question :-

3x-4y=18

4x - 5y=22

eliminate y by cofficient method

Required Answer :-

3x-4y=18-(i)

4x-5y=22-(ii)

multiply equation (i) by 5 and equation (ii) by 4,

3x-4y=18 4x-5y=22

3x-4y=18 4x-5y=22

x 5 and x 4

___________ _____________

15x-20y=90-(iii) 16x - 20y = 88

subtract equation(iii) and (iv)

15x-20y=90

-16x+20y=-88

____________

-x=2

x= -2

put x=2 in equation(i)

3x - 4y = 18

183 (-2) - 4y = 18

18- 6 - 4y = 18

18- 4y = 18 + 6

6- 4y = 24

24- y = 24/4

24/4- y = 6

y = -6

therefore (x,y)=(-2,-6) is the solution

Hope it help you :)

Be brainly!!