Answer:
-2, 3, -0.5 + 0.866i, -0.5 - 0.866i.
Step-by-step explanation:
As the last term is -6 , +/- 2 , +/- 3 are possible zeroes.
Try 2:-
(2)^4 - 6(2)^2 - 7(2) - 6 = -28 so 2 is not a zero.
3:-
(3)^4 - 6(3)^2 - 7(3) - 6 = 0 so 3 is a zero.
(-2)^4 - 6(-2)^2 - 7(-2) - 6 = 0 so -2 is also a zero.
Divide the function by (x +2)(x - 3), that is x^2 - x - 6
gives x^2 + x + 1
x^2 + x + 1
So we have x^2 + x + 1 = 0
x = [-1 +/- √(1^1 - 4*1*1)] / 2
= -1 + √(-3) / 2 , - 1 - √(-3) / 2.
= -0.5 + 0.866i, -0.5 - 0.866i
Joanna bought 7 notebooks and 14 pencils
Step-by-step explanation:
Step 1 :
Let x denote the number of notebooks and y denote the number of pencils Joanna bought.
Cost of one notebook = $ 2.30
Cost of one pencil = $1.42
Step 2 :
Total of notebooks and pencils bought = 21
=> x + y = 21 => y = 21-x
Total cost of notebooks and pencils = $35.98
=> 2.3x + 1.42y = 35.98
Substituting y = 21- x here , we have,
2.3x + 1.42 ( 21-x) = 35.98
2.3x + 29.82 - 1.42x = 35.98
0.88 x = 6.16
=> x = 7
y = 21-x = 21-7 = 14
Step 3 :
Answer :
Joanna bought 7 notebooks and 14 pencils
Answer:
5.75
Step-by-step explanation:
4) 230 ÷ 40 = 5.75
It increases the mean value of the prizes.
