math
posted by Kyle on .
Solve the system
x^2+y^24x+2y=20
4x +3y =5

Rewrite
x^2+y^24x+2y=20
as
(x2)^2+(y+1)^2=25=5^2 ...(1)
represents a circle of radius 5 with centre (2,1).
which intersects with the line
4x+3y=5 ...(2)
So write
y=(54x)/3 and substitute in the circle equation (1)
to get (x2)^2+(((54x)/3)+1)^2=5^2
Solve for x in the above quadratic to get:
x=5 or x=1
Find y accordingly.