SOLUTION: Find the real roots of each equation. 25x^2-49=0 And 16x^2+8=9 And 8y^3+125=0

Algebra ->  Rational-functions -> SOLUTION: Find the real roots of each equation. 25x^2-49=0 And 16x^2+8=9 And 8y^3+125=0      Log On


   

Question 867700: Find the real roots of each equation.
25x^2-49=0
And
16x^2+8=9
And
8y^3+125=0
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
25x^2-49=0
(5x)^2 - 7^2 = 0 (difference of squares)
(5x-7)(5x+7) = 0
x = {-7/5, 7/5}
And
16x^2+8=9
16x^2-1=0
(4x)^2 - 1^2 = 0 (difference of squares)
(4x-1)(4x+1) = 0
x = {-1/4, 1/4}
And
8y^3+125=0
(2y)^3 + 5^3 = 0 (sum of cubes)
(2y+5)(4y^2-10y+25) = 0
the only real zero is at
y = -5/2