Question

2y - x = 0 ; 10x + 15y = 105

Answer 1

2y-x=0.................1

10x+15y=105......2

2y-x=0

15y+10x=105

30y-x=0...............3

30y+20x=210......4

-21x=-210

x=10

putting value of x in equation 1:

2y-(10)=0

2y-10=0

y=5

Hence:

x=10, and

y=5

Answer 2

Answer:

2y − x = 0 ⇒x=2y .....(I)

10x + 15y = 105 .....(II)

Taking out 5 common from (II)

2x+3y=21 .....(III)

From (I) and (III)

2(2y)+3y=21

⇒4y+3y=21

⇒7y=21

⇒y=3

x=2×3

=6