Answer:
C(5,-9) and r=8.
Step-by-step explanation:
C(p, q) - center
r=radius
k:x^2 +y^2 +dx+ey+f=0
x^2+y^2 - 10x+18y+42=0
d=-10, e=18, f=42
p=-d/2=-(-10)/2=10/2=5
q=-e/2=-18/2=-9
r^2 =p^2+q^2-f
r^2 =5^2 +(-9)^2 - 42
r^2=25+81-42
r^2 =106-42
r^2 =64
r=sqrt(64)
r=8
C(p,q)=C(5,-9) r=8
2(x+y)=24
2x=y
Use substitution. If y=2x, than we can substitute 2x for it in the other equation, because x and y equal the same things in both equations.
So using that we get 2(x+2x)=24
SIMPLIFY
2(3x)=24
DISTRIBUTE
6x=24.
DIVIDE: x=4.
If we substitute x into the original equations we get x=4 and y=8. Those are your two numbers.
Have a nice day! :)
