solving system by substitution

Solving System By Substitution class=

Answer :

Answer:

The solution of this system is (9, 2).

Step-by-step explanation:

Substitute x - 7 for 'y' in the first equation.  We get:

x - 3(x - 7) = 3           Doing this temporarily eliminates the variable 'y'.

Now perform the indicated multiplication, and then combine like terms:

x - 3x + 21 = 3, or

-2x = -18

so that x = 9.  Substituting 9 for x in the second equation, we get:

y = 9 - 7, or y = 2.  

The solution of this system is (9, 2).