JoseeMx
contestada

Caprice adds equations A and B to solve this system of equations. What makes this approach a valid method in general for solving a system of equations?

Caprice adds equations A and B to solve this system of equations What makes this approach a valid method in general for solving a system of equations class=

Respuesta :

Answer: Because the y terms cancel

Step-by-step explanation:

Hi, this approach is called the addition method.

By adding both equations we can cancel one term that contains one variable, and calculate the remaining variable.

For example, in this case:

8x + 3y = 27

+

4x-3y = 9

_______

12x = 36

Now, we can solve for x:

x = 36/12

x = 3

Now, simple replace the value of x in any equation to obtain the value of y:

4x-3y = 9

4(3)-3y =9

12-3y =9

12-9 = 3y

3 =3y

3/3 =y

y=1