posted by shawn on .
Please type your subject in the School Subject box. Any other words, including obscure abbreviations, are likely to delay responses from a teacher who knows that subject well.
I would insist that by 12th grade you would recognize the difference of squares pattern.
Problem x4 - 16 = 0
FIRST. Make [x4 - 16] a perfect square.
Dive -16 by two and square that number, add to both sides.
x4 -16 + 64 = 0 + 64
SECOND. Solve the equation.
(Simplify) → (x2 - 8)^2 this equal the left side of the equation.
so we have
(x2 -8)^2 = 64
Remove the square by taking the square root of 64.
x2 - 8 = positive or negative 8
And then find your answers.
Giving the solutions
(i being the imaginary unit)