Answers
1) 4
2) 0, 2, -10
3) 0, 5, -2
Step-by-step explanation:
1) x³ - 64 = 0
x³ = 64
x = 4
2) x³(x² + 8x - 20) = 0
x³(x² + 10x - 2x - 20) = 0
x³(x(x + 10) - 2(x + 10)) = 0
x³(x + 10)(x - 2) = 0
x = 0, 2, -10
3) x³ - 3x² - 10x = 0
x(x² - 3x - 10) = 0
x(x² - 5x + 2x - 10) = 0
x(x(x - 5) + 2(x - 5)) = 0
x(x - 5)(x + 2) = 0
x = 0, 5, -2
Perhaps the most concise way to factor is by "completing the square" which is how the quadratic formula is derived...
x^2+6x+8=0 move constant to other side, subtract 8 from both sides
x^2+6x=-8, halve the linear coefficient, square it, then add that to both sides, in this case (6/2)^2=3^2=9
x^2+6x+9=1 now the left side is a perfect square of the form
(x+3)^2=1 take the square root of both sides
x+3=±√1 subtract 3 from both sides
x=-3±√1
x=-3±1
x=-4 and -2
Since the zeros occur when x=-4 and -2 the factors of the equation are:
(x+2)(x+4)
Answer:
5n^2 - 3n - 8
Step-by-step explanation:
4n.5n - 4n.8 + 4.5n - 4.8
= 20n^2 - 32n + 20n - 32
= 20n^2 - 12n - 32
= 4 ( 5n^2 - 3n - 8 )
= 5n^2 - 3n - 8 [ answer ]
I think the answer is 32 if I did my math right sorry if it wrong
