what is 8s+12t=16, 6s+9t=12 in substitution method

Question

solve 8s+12t=16, 6s+9t=12 using the substitution method.

Answer 1

8s + 12t= 16,  2s +3t= 4

6s +9t= 12, 2s + 3t= 4

* It is the same equation, I don't have enough information

Comments

It means there are infinitely many solutions, and they can be represented by a straight line graph s=(4-3t)/2.

Answer 2

 

1. 8s+12t=16, 6s+9t=12

Let,

8s+12t=16 ---------------(1)

    6s+9t=12 -----------------(2)

From equation (1) we get ,

 8s+12t=16

or. 8s=16-12t

or, s= 16-12t/8 = 4-3t/2

   

 

Substituting   s= 4 - 3t/2  in eq. no. (2) we get,

 

6× 4-3t/2+9t=12

or,  3(4-3t)+9t=12

or, 12-9t+9t=12

 

Comments

You got 0=0, which is true, so although there appears to be two equations, there's really only one, so you have a many-solutions situation, infinitely many. They can be represented by a straight line graph s=(4-3t)/2.