Answer:
The roots are real and unequal (3, -3)
Step-by-step explanation:
x²-9=0
ax²+bx+c=0
Comparing we get,
a= 1
b= 0
c = -9
Determinant: b²-4ac
= 0² - 4(1)(-9)
= 36>0
D > 0
Therefore, the equation has real and unequal roots.
Algebraic identity:
x² - a² = (x-a)(x+a)
Using this identity
x²-9 = (x+3)(x-3)
Roots are 3 and -3 which are real and not equal to each other
Hope this answer helps you ..
I think is B but I have to work this out
1) 2.92• 10^-3 2) 2.16•10^7. 3)7.5•10^8
