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3 years ago

10

Solve 2x2 − 8x = −7.

2 answers:

maks197457 [2]3 years ago

8 0

Answer:

D.2 plus or minus the square root of 2 end root over 2

Step-by-step explanation:

leva [86]3 years ago

7 0

$\sf 2x^2 - 8x = - 7 \\ \\ Subtract \ -7 \ from \ both \ sides \ of \ the \ equation. \\ \\ 2x^2 - 8x - (-7 ) = - 7 - (-7) \\ \\ 2x^2 - 8x + 7 = 0 \\ \\ Use \ quadratic \ formula \ a = 2, b = -8, c = 7 \\ \\ x = \dfrac{- b \pm \sqrt{b^2- 4ac} }{2a} \\ \\ \\ x = \dfrac{-(-8) \pm \sqrt{(-8)^2 - 4 (2) (7) } }{2(2)} \\ \\ x = \dfrac{8 \pm \sqrt{8} }{4} \\ \\ x = 2 + \frac{1}{2}\sqrt{2} \ or \ x = 2 + \frac{-1}{2} \sqrt{2}$

Ur answer is the fourth one

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A department store buys 500 shirts at a cost of $3,500 and sells them at a selling price of $10 each. Find the percent markup.

Ratling [72]

Answer: 30 percent.

Step-by-step explanation: First do 3,500 divided by 10 to find the cost of each shirt. Second subtract 7 from 10 which is 3. Then divide 3 by ten because you always divide by the amount being paid for. So 3 divided by 10 is .3 then multiply .3 by 100 which is 30 and that is your percent markup

5 0

3 years ago

Find the lateral area of the cone in terms of π.

Andreyy89

Answer:

$15\pi\ cm^{2}$

Step-by-step explanation:

we know that

The lateral area of the cone is equal to

$LA=\pi rl$

where

r is the radius of the base

l is the slant height

we have

$r=3\ cm$

Applying the Pythagoras Theorem find the slant height

$l^{2}=3^{2} +4^{2}\\ \\l^{2}=25\\ \\l=5\ cm$

substitute in the formula

$LA=\pi (3)(5)=15\pi\ cm^{2}$

8 0

3 years ago

find x if the distance between points L and M is 15 and point M is located in the first quadrant. L=(-6,2) M=(x,2)

aivan3 [116]

Answer:

Therefore,

$x = 9$

Step-by-step explanation:

Given:

Let,

point L( x₁ , y₁) ≡ ( -6 , 2)

point M( x₂ , y₂ )≡ (x , 2)

l(AB) = 15 units (distance between points L and M)

To Find:

x = ?

Solution:

Distance formula between Two points is given as

$l(LM)^{2} = (x_{2}-x_{1})^{2}+(y_{2}-y_{1})^{2}$

Substituting the values we get

$15^{2}=(x--6)^{2}+(2-2)^{2}\\\\225=(x+6)^{2}$

Square Rooting we get

$(x+6)=\pm \sqrt{225}=\pm 15\\\\x+6 = 15\ or\ x+6 = -15\\\\x= 9\ or\ x = -21$

As point M is located in the first quadrant

x coordinate and y coordinate are positive

So x = -21 DISCARDED

Hence,

$x = 9$

Therefore,

$x = 9$

3 0

3 years ago

A book costs $ 25.Marilyn bought the book during a sale 15% discount. How much did she pay for the book

blondinia [14]

The price of the discount is $25 x 0.15 = $3.75
The price of the book with discount is $25 - $3.75 = $21.25

5 0

3 years ago

In circle M with m \angle LMN= 98m∠LMN=98 and LM=18LM=18 units, find the length of arc LN. Round to the nearest hundredth.

Feliz [49]

Answer:

To the nearest hundredth, this is 30.79 units

Step-by-step explanation:

To find the length of the arc, we simply apply the length of arc formula

Mathematically, that would be;

theta/360 * 2 * pi * r

Theta here is 98

r is 18 units

So the length of the arc will be;

98/360 * 2 * 22/7 * 18

= 30.7876 units

to the nearest hundredth, this is;

30.79 units

5 0

3 years ago