+12 Solve each of the following systems of equations. Find all solutions and explain.
(a)x+y=−1,3x=4−3y.
(b)3x−4y+2=0,10−10y=10y−15x.
+214 The first one: separate y in both of them to set the equations equal.
y=-1-x
y=4/3-x
Then
4/3-x=-1-x
4/3=-1
Since that is not true, there are no solutions to the first system of equations.
The second one:
3x+2=4y
3x/4+1/2=y
20y=10+15x
y=1/2+3x/4
Then
3x/4+1/2=3x/4+1/2
So, since that is true for all x, any (x,y) that matches the first equation matches the second one as well.
