Question

How do you solve this by elimination method? 4x+3y=016x+3=8y

Answer 1

4 x + 3 y = 0

16 x + 3 = 8y
______________

Multiply the first equation by 4

16 x + 12 y = 0

16 x + 3 = 8y
______________

Subtract 8 y by second equation

16 x + 12 y = 0

16 x + 3 - 8 y = 8y - 8y = 0
______________

16 x + 12 y = 0

16 x + 3 - 8 y = 0
______________

Subtract 3 by second equation

16 x + 12 y = 0

16 x + 3 - 8 y - 3 = 0 - 3
______________

16 x + 12 y = 0

16 x - 8 y = - 3
________________

Subtract fsecond equation from first equation

16 x - 1 6 x + 12 y - ( - 8 y ) = 0 - ( - 3 )

12 y + 8 y = 3

20 y = 3 Divide both sides by 20

y = 3 / 20

Put y = 3 / 20 in first equation.

4 x + 3 y = 0

4 x + 3 * 3 / 20 = 0

4 x + 9 / 20 = 0 Subtract 9 / 20 by both sides

4 x + 9 / 20 - 9 / 20 = 0 - 9 / 20

4 x = - 9 / 20 Divide both sides by 4

x = - 9 / ( 20 * 4 )

x = - 9 / 80


Solution :

x = - 9 / 80 , y = 3 / 20