Answer:
The following are the solution to the given points:
Step-by-step explanation:
Given value:

Solve point 1 that is
:
when,







Calculate the sum 


When 


In point 2: 
when,







calculate the sum:

when 


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
Answer:
- width: 18 in
- length: 27 in
Step-by-step explanation:
The relations between length (L) and width (W) are ...
W +9 = L
LW = 486
Substituting gives ...
(W+9)W = 486
W^2 +9W -486 = 0 . . . put in standard form
(W +27)(W -18) = 0 . . . . factor
W = 18 . . . . the positive solution
The width of the rectangle is 18 inches; the length is 27 inches.
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<em>Comment on factoring</em>
There are a number of ways to solve quadratics. Apart from using a graphing calculator, one of the easiest is factoring. Here, we're looking for factors of -486 that have a sum of 9.
486 = 2 × 3^5, so we might guess that the factors of interest are -2·3² = -18 and 3·3² = 27. These turn out to be correct: -18 +27 = 9; (-18)(27) = -486.