>>27840076So we have .05X+.08Y=2100
And 30000 = X+Y
So Y= 30000 - X
So back in the original equation
.05X+.08(30000-X) = 2100
And we solve for X.
.05X+2400-.08x = 2100
-2400 from both sides
(.05-.08)x= -300
-.03x = -300
X=9
And back to X+Y=30,000
X=9
Y=29,991