Question

1.4x+3.9y=6.4
0.2x-1.3y=1.2
solve using substitution method

Answer 1

HI :DDD

Answer 2

The substitution method asks you to find what either x or y equals, and to then take that whole equality and substitute if for either your x or your y in the other equation.

In this case, since I loathe decimals, I'm going to scale each equation by a factor of ten to give:

14x + 39y = 64
2x - 13y = 12

The easiest to find a substitution for is x, using the second equation. We can see that 2x - 13y = 12 can be rewritten as 2x = 13y + 12, and so x = 13/2 y +6.

Thus we substitute x = 13/2 y + 6 into our first equation, to give:

14(13/2 y + 6) + 39y = 64

I'll leave it there since from thereon this is just simplifying and solving, but let me know if you'd like the completed solution.