Question

Y = 4x2 - 16 has how many real roots?
A. 0
B. cannot be determined
C.1
D.2

Answer 1

2 real roots

Explanation:

y = 4x2 - 16

Set equal to zero

0 = 4x2 - 16

Add 16 to each side

16 = 4x^2

Divide by 4

16/4 = 4x^2/4

4 = x^2

Take the square root of each side

sqrt(4) = sqrt(x^2)

±2 =x

There are 2 real roots