4x+y=3.4 x=4y

Question

It's solving systems by substitution 

Answer 1

Adam,

 

Substitute 4y for x in the first equation:

 

4(4y) + y = 3.4  (I hope that really is 3.4!)

 

16y + y = 3.4

 

17y = 3.4

 

y = 3.4/17 = 0.2

 

Then, substitute 0.2 for y in x = 4y to get the x solution.

 

x = 4(0.2) = 0.8.

 

The solution is x = 0.8, y = 0.2. This is sometimes written as an ordered pair: (0.8, 0.2).