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zloy xaker [14]
3 years ago
10

PLEASE HELP!!! Find a quadratic model for the set of values: (-2, -20), (0, -4), (4, -20). Show your work.

Mathematics
1 answer:
Mice21 [21]3 years ago
3 0
Alright

so we have a set of points

any quadratic function can be represeted by the form
y=ax²+bx+c
where a, b, and c are all constants
sometimes we use f(x) instead of y

anyway

we can find the values of a, b, and c by subsituting the points


ok
for (-2,-20)
x=-2 and y=-20
-20=a(-2)²+b(-2)+c or
-20=4a-2b+c

for (0,-4)
x=0 and y=-4
-4=a(0)²+b(0)+c
-4=c
neato
we can subsitute -4 for c later to find a and b later

using (4,-20)
x=4 and y=-20
(at this point we notice that (-2,-20) and (4,-20) have same y values so the x value of the vertex will be the midpoint of the 2 x values which is at x=1 and we can do math to find the other things but whatever)
x=4 and y=-20
-20=a(4)²+b(4)+c
-20=16a+4b+c


alright

we've got
-20=4a-2b+c
-4=c
-20=16a+4b+c

usinb -4=c
-20=4a-2b-4
-20=16a+4b-4
add 4 to everybody
-16=4a-2b
-16=16a+4b
elimination

multiply top equation by 2 and add to 2nd equation
-32=8a-4b
-16=16a+4b +
-48=24a+0b

-48=24a
divide both sides by 24
-2=a
sub back into one of the equations
-16=4a-2b
-16=4(-2)-2b
-16=-8-2b
add 8
-8=-2b
divide by -2 both sides
4=b

a=-2
b=4
c=-4

y=-2x²+4x-4
or
f(x)=-2x²+4x-4
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The answer is <em>1</em>.

Step-by-step explanation:

Given the expression:

|z-6|-|z-5|,\ if\ z

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First of all, let us learn about the absolute value function:

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Here the given expression contains two absolute value functions:

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Using the definition of absolute value function as per above definition.

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So, given expression |z-6|-|z-5|,\ if\ z will be equivalent to :

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• 99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ.

Mean of 98.35°F and a standard deviation of 0.64°F.

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= 96.43°F

μ + 3σ.

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b. What is the approximate percentage of healthy adults with body temperatures between 97 .71°F and 98.99°F?

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16 es tu repuesta

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