Use the substitution method to solve the system of equation 4x-8y=0..x^2+y^2=25..........5 stars best answer

STEP I: solve the equation 4x-8y=0 for x. show your work. x=_______________________

STEP II: substitute the expression you found for x in step 1 into the equation x^2+y^2=25. then solve for y . show your work..(___________)+y^2=25

STEP III: once you know the values of y, substitute them back into the first equation to find the corresponding values of x. show your work.

STEP IV: write your solution as ordered pairs.
(_______ ________) and (_______,________)

I. 4x - 8y = 0
4x = 8y
x = 2y

II. (2y)^2 + y^2 = 25
4y^2 + y^2 = 25
5y^2 = 25
y^2 = 5
y = ± √5

III. x = ± 2√5

IV. (2√5, √5) (-2√5, -√5)