1. Answer: x < –4
The question is a bit ambiguous since x4 can be interpreted as x^4. Since there was no option for −x^4−6 ≥ −8 , I will solve the question assuming that the original question was −x(4−6)≥−8
−x(4−6)≥−8 −x(-2)≥−8 ---> multiply x with -2 2x≥−8 ----> divide by 2x≥−4
2. Answer: x≥ -11
To solve inequality using > or < sign, you must be careful because multiplying the inequality with -1 will cause the sign to change direction(< will become > or vice versa). In this case, will solve the question without multiplying it with -1
6.7 ≥−0.2x + 4.5 ----> move -0.2x to left, 6.7 to right
0.2x ≥ 4.5 - 6.7
0.2x ≥ -2.2
x≥ -11
Answer: 81% of the variance in dependent variable is explained by this correlation .
Step-by-step explanation:
For X = Independent variable and Y=dependent variable,
If r= correlation coefficient , then we say
<em> </em>of the<em> </em>variance in Y is explained by Variable X.
Given: r= 0.90

So, 81% of the variance in dependent variable is explained by this correlation .
Let's to the first example:
f(x) = x^2 + 9x + 20
Ussing the formula of basckara
a = 1
b = 9
c = 20
Delta = b^2 - 4ac
Delta = 9^2 - 4.(1).(20)
Delta = 81 - 80
Delta = 1
x = [ -b +/- √(Delta) ]/2a
Replacing the data:
x = [ -9 +/- √1 ]/2
x' = (-9 -1)/2 <=> - 5
Or
x" = (-9+1)/2 <=> - 4
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Already the second example:
f(x) = x^2 -4x -60
Ussing the formula of basckara again
a = 1
b = -4
c = -60
Delta = b^2 -4ac
Delta = (-4)^2 -4.(1).(-60)
Delta = 16 + 240
Delta = 256
Then, following:
x = [ -b +/- √(Delta)]/2a
Replacing the information
x = [ -(-4) +/- √256 ]/2
x = [ 4 +/- 16]/2
x' = (4-16)/2 <=> -6
Or
x" = (4+16)/2 <=> 10
______________
Now we are going to the 3 example
x^2 + 24 = 14x
Isolating 14x , but changing the sinal positive to negative
x^2 - 14x + 24 = 0
Now we can to apply the formula of basckara
a = 1
b = -14
c = 24
Delta = b^2 -4ac
Delta = (-14)^2 -4.(1).(24)
Delta = 196 - 96
Delta = 100
Then we stayed with:
x = [ -b +/- √Delta ]/2a
x = [ -(-14) +/- √100 ]/2
We wiil have two possibilities
x' = ( 14 -10)/2 <=> 2
Or
x" = (14 +10)/2 <=> 12
________________
To the last example will be the same thing.
f(x) = x^2 - x -72
a = 1
b = -1
c = -72
Delta = b^2 -4ac
Delta = (-1)^2 -4(1).(-72)
Delta = 1 + 288
Delta = 289
Then we are going to stay:
x = [ -b +/- √Delta]/2a
x = [ -(-1) +/- √289]/2
x = ( 1 +/- 17)/2
We will have two roots
That's :
x = (1 - 17)/2 <=> -8
Or
x = (1+17)/2 <=> 9
Well, this would be your answers.
Answer:
$13.76
Step-by-step explanation:
i used a calculator to find 25% of $55.05
Answer:

Step-by-step explanation:


