Question

2x+3y=15
x+y=6
work out the values of x and y

Answer 1

x = 3

y = 3

Explanation:

2x + 3y = 15

x + y = 6

2x + 3y = 15

x(-3) + y(-3) = 6(-3)

2x + 3y = 15

-3x - 3y = -18

Add:

2x + 3y = 15

-3x - 3y = -18

- x = -3

x = 3

Substitute x to any of the equation:

x + y = 6

3 + y = 6

y = 6 - 3

y = 3

Answer 2

x=3

y=3

Explanation:

x = 6-y

-plug in (6-y) into first equation

2(6-y)+3y = 15

12-2y+3y=15

-2y+3y = 3

y=3

x=6-3

x=3

double check:

(2*3) + (3*3) = 6 + 9 = 15

3 + 3 = 6