Question 950397
go about solving these linear equations using substitution 
4x-y=5
 4x+4y=-4
----
Modify::
y = 4x-5
x + y = -1
-------------------
Substitute for "y" and solve for "x"::
x + 4x-5 = -1
----
5x = 4
x = 4/5
----
Solve for "y"
x + y = -1
4/5 + y = -1
y = -9/5
--------------
Cheers,
Stan H.
--------------