Function: 12+0.5x
12+0.5x=18.5
0.5x=6.5
x=13 days
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
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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
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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:
screw this question
Step-by-step explanation:
To change from 15% to 25% he needs to add 10%.
If the solution is 50ml then he needs to add 10% which is 5ml... But if he adds 5 ml then the solution will be 55ml total, so that doesn't make sense. He has to take some of the solution that's not acid before adding the 5ml...
Answer: The area common to both triangle is 31.77 sq. cm.
Step-by-step explanation:
Since we have given that
30-60-90 triangles are placed.
So, the ratio of sides would be

Since Hypotenuse = 12 cm
So, it becomes,

So, Base would be

and Perpendicular would be

So, Area common to the both triangles would be

Hence, the area common to both triangle is 31.77 sq. cm.
The arrangement of the numbers in the ascending order will be 11, 13, and 17.
The complete question is given below.
<h3>What is Algebra?</h3>
The analysis of mathematical representations is algebra, and the handling of those symbols is logic.
Ali picked a three number from a hat.
The lowest number was 11.
The range was 13.
The median was 17.
The arrangement of the numbers in the ascending order. Then we have,
11, 13, and 17.
The arrangement of the numbers in the ascending order will be 11, 13, and 17.
More about the Algebra link is given below.
brainly.com/question/953809
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