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3 years ago

HELP ASAP PLEASE!!!

Mathematics

1 answer:

grigory [225]3 years ago

7 0

The quadratic fomula:

$ax^2+bx+c=0\\\\\Delta=b^2-4ac\\\\If\ \Delta0,\ then\ \boxed{TWO\ SOLUTIONS:\ x_1=\dfrac{-b-\sqrt\Delta}{2a}\ and\ x_2=\dfrac{-b+\sqrt\Delta}{2a}}-----------------------------------------------$

We have the equation:

$2x^2-7x-21=0\\\\a=2,\ b=-7,\ c=-21\\\\\Delta=(-7)^2-4(2)(-21)=49+168=217 > 0\\\\x_1=\dfrac{-(-7)-\sqrt{217}}{2(2)}=\dfrac{7-\sqrt{217}}{4}\approx-1.93\\\\x_2=\dfrac{-(-7)+\sqrt{217}}{(2)(2)}=\dfrac{7+\sqrt{217}}{4}\approx5.43\\\\Answer:\ \boxed{\boxed{2.\ -1.93\ and\ 5.43}}$

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ExtremeBDS [4]

Answer:

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Step-by-step explanation:

step 1

Find the equation of the first inequality

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substitute the values

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The equation in slope intercept form is equal to

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we have

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substitute

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Remember that

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The inequality is

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step 2

Find the equation of the second inequality

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we have the ordered pairs

(0,2) and (4,0)

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The formula to calculate the slope between two points is equal to

$m=\frac{y2-y1}{x2-x1}$

substitute the values

$m=\frac{0-2}{4-0}$

$m=\frac{-2}{4}$

$m=-\frac{1}{2}$

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we have

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$b=2$ ---> the y-intercept is given

substitute

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Remember that

Everything below and to the left of the line is shaded

The inequality is

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Rewrite

Multiply by 2 both sides

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therefore

The system of inequalities is

$y\geq x-2$

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see the attached figure to better understand the problem

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3 years ago

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Alenkinab [10]

1/3÷3/8

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2 years ago

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alexgriva [62]

Answer:

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Step-by-step explanation:

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miss Akunina [59]

Answer:

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Step-by-step explanation:

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noname [10]

Answer:

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Step-by-step explanation:

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