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3 years ago

HELP FAST !!!

Mathematics

2 answers:

leonid [27]3 years ago

7 0

Answer:

(x, y) = (9, 10)

Step-by-step explanation:

-8x + 7y = -2...... (1)

- 8x + 8y = 8......(2)

Multiplying on both sides of the equations (1) & (2) by 8 and 7 respectively, we find:

-64x + 56y = - 16...(3)

-56x + 56y = 56.....(4)

Subtracting equation (4) from equation (3), we find:

-64x + 56y = - 16

-56x + 56y = 56

+ - -

_____________

- 8x = - 72

x = - 72/-8

x = 9

Substituting x = 9 in equation (1), we find:

-8(9) +7y = - 2

-72 +7y = - 2

7y = 72 - 2

7y = 70

y = 70/7

y = 10

(x, y) = (9, 10)

sertanlavr [38]3 years ago

3 0

-56x + 49y= -14

- 56x + 56y=64

105y=50

y=0.48

-8x+7(0.48)=-2

-8x+3.36=-2

-8x=-5.36

x=0.67

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The area of a rectangular field is 6840 m2. If the width of the field is 72m , what is its length?

IgorLugansk [536]

Answer:

I believe that the answer is 95 meters.

Explanation:

Okay, so to solve this question, you must know the formula to solve for the area of a rectangle/square.

Area of a rectangle/square - l x w

In this question, you can see the the width (72 m) and the area (6840 m²) is already given. What you can do in this situation is to use the opposite operator (division) to solve for the length of the rectangular field.

6840 ÷ 72 = 95

You can always double check to see if the number is correct.

A = l x w

= 72 m x 95 m

= 6840 m²

Really hope this helped. :)

6 0

3 years ago

Abigail tosses a coin off a bridge into the stream below. The distance, in feet, the coin above the water is modeled by the equa

melomori [17]

Answer:

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Step-by-step explanation:

Distance of the coin above the water is modeled by the equation

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where $x$ is time taken to cover the distance

Now equating with zero.

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