solve 6x-y=12 and 3x+y=15

Question

6x-y=12

3x+y=15

a. (6,3)

b(1,-6)

c. (1,12)

d. (3,6)

Answer 1

Elimination method

Given equations are 6x-y = 12 ---> (1)

3x+y = 15 ---> (2)

To eliminate y value add the equations (1)&(2).

6x-y = 12

3x+y = 15

____________

9x = 27

Divide to each side by 9.

x = 3

Substitute the x value in (2).

9+y = 15

Subtract 9 from each side.

y = 6

Solution x = 3, y = 6.

Option d is correct choice.