Sagot :
[tex]y=4x^2-64=4(x^2-16)=4(x^2-4^2)=4(x-4)(x+4)\\\\-------------------------------\\\\4(x-4)(x+4)=0\iff x-4=0\ or\ x+4=0\\\\x=4\ or\ x=-4[/tex]
Answer:
x = 4
x = - 4
Step-by-step explanation:
y = 4x² - 64
y = 4(x² - 4²)
4(x - 4)(x + 4)
Two separate equations
x - 4 = 0
x + 4 = 0
x - 4 = 0
x - 4 + 4 = 0 + 4
x = 4
x + 4 = 0
x + 4 - 4 = 0 - 4
x = - 4