Question

Solve the equations by substitution method: A) x+y=3, 2x+5y=12.​

Answer 1

Answer:

x = 1, y = 2

Step-by-step explanation:

Original equations:

$x+y=3\\2x+5y=12$

Substitute y and solve for x:

$y=3-x\\2x+5y=12$

$2x+5(3-x)=12$

$2x+15-5x=12$

$-3x=-3$

$x=1$

Plug in x to solve for y:

$1+y=3$

$y=2$

x = 1, y = 2

Note: You can also substitute x and solve for y, then plug in y to solve for x. I did not do that here.

Answer 2

Answer:

x+y=3

x=3-y equation 1

2x+5y=12

2(3-y)+5y=12

6-2y+5y=12

6+3y=12

3y=12-6

y=6÷3

y=2 equation 2

again ,

putting value of equation 2 in equation 1

x=3-y

x=3-2

x=1