Using distributive property, we get:
3x-9=0
3x=9
x=3
So, x=3. Now that was easy, huh? :)
This is the difference of 2 squares
square root of a^6 = a^3
and square root of 25 b^2 = 5b so we get
(a^3 + 5b)(a^3 - 5b)
Thats the answer
The answer should be 4. Take note of the pattern of unit digits of 2^n.
2^1 = 2
2^2 = 4
2^3 = 8
2^4 = 16
2^5 = 32
Every 4 powers, it rotates 2, 8, 6, 4. Since 2020 is divisible by 4, the answer is 4.
(−∞,∞) infinite solutions