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3 years ago

8x - 6y = -20 -16х +7 y = 30

Mathematics

2 answers:

Irina-Kira [14]3 years ago

8 0

Answer:

(-1,2)

Step-by-step explanation:

multiply top equation by 2 and add them together as follows

16x-12y=-40

-16x+7y=30

-5y=-10

y=2

now replace y with 2 in the first equation and solve for x

8x-6(2)=-20

8x-12=-20

8x=-8

x=-1

Ivahew [28]3 years ago

4 0

Answer:

8x - 6y = 20-16х +7 y = 30

Step-by-step explanation:

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Which of the following explains how to use partial quotients to find 832 ÷ 26 ?

jeyben [28]

Answer:

C. Subtract 30 × 26 from 832 to get 52. Then subtract 2 x 26 from 52 to get 0.

Then add the partial quotients 30 + 2 to get 32. The quotient is 32.

Step-by-step explanation:

The attached shows the use of partial quotients to create the next dividend in the long division process. Each quotient digit is multiplied by the divisor and that product is subtracted from the dividend to create the next dividend. Then the process is repeated.

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Here, the correct answer choice is the only one that has the correct quotient.

3 0

3 years ago

Solve the equation. 8x2 – 4 = 28

Flura [38]

Hello,

Your answer would be 2, -2.

$8x^2 - 4 = 28$

$8x^2-4+4=28+4$

$8x^2 = 32$

$\frac{8x^2}{8}= \frac{32}{8} 
$

$x^2 = 4$

x = +/4

x = 2 or x = -2

2 , -2 would be the answer! :)

Mark Brainliest if this helped you :)

4 0

3 years ago

Read 2 more answers

Plz answer question in screen shot

lisov135 [29]

Answer:

200√3

Step-by-step explanation:

The triangle given here is a special right triangle, one with angles measuring 30-60-90 degrees. The rule for triangles like these are that the side opposite the 30° angle can be considered x, and the side opposite the 60° angle is x√3, while the hypotenuse, or side opposite the right angle, is 2x. All we need to know here are the two legs to find the area.

Since b is opposite the 30° angle, it is x, while side RS is opposite the 60° angle, meaning it is equal to x√3, meaning that the area of the triangle is 1/2*x*x√3. We can substitute in 20 for x, making our area 1/2*20*20√3. Multiplying we get 10*20√3, or 200√3.

6 0

4 years ago

An open top rectangular box is to be made from a rectangular piece of metal that is 3cm wide and 8cm long by cutting a square fr

Tanzania [10]

Answer:

x = 0.67 cm

Step-by-step explanation:

Let call " x " the length of the side of the square to cut from each corner

then the sides of the future box would be

L = 8 - 2x and D = 3 - 2x

The volume of the box is:

V = L*D*x

And such volume as function of x is

V(x) = ( 8 - 2x ) * ( 3 - 2x ) * x ⇒ V(x) = ( 24 - 16x - 6x + 4x²) * x

V(x) = 4x³ - 22x² + 24x

Taking derivatives on both sides of the equation we get:

V´(x) = 12x² - 44x + 24

Then V´(x) = 0 ⇒ 12x² - 44x + 24 = 0 ⇒ 3x² - 11x + 6 = 0

We got a second degree equation solving for x

x₁,₂ = [11 ± √ 121 - 72 ] / 6

x₁ = ( 11 + 7 ) / 6 x₁ = 3 we dismiss this solution since according to problem statement one side would become negative

Then

x₂ = ( 11 - 7 ) / 6 ⇒ x₂ = 4/6 ⇒ x₂ = 0.67 cm

As the second drivative is smaller than 0 then there is a maximun in that point

V´´(x) = 12x - 44 < 0

Sides of the box

L = 8 - 2x ⇒ L = 8 - 2*(0.67) ⇒ L = 8 - 1.34 ⇒ L = 6.66 cm

D = 3 - 2x ⇒ D = 3 - 2* (0.67) ⇒ D = 3 - 1.34 ⇒ D = 1.66 cm

Heigh = x = 0.67 cm

V(max) = 6.66*1.66*0.67

V(max) = 7.41 cm³

5 0

3 years ago

Find the volume of a cone

Alja [10]

The volume is <span>1658 hope it helps <3</span>

4 0

3 years ago