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2 years ago

Solve the simultaneous equations 8 x + 5 y = 28 4 x + 5 y = 16

Mathematics

2 answers:

umka21 [38]2 years ago

8 0

Answer: x=3, y=4/5 or 0.8

Step-by-step explanation:

To find x and y, you can use elimination.

8x+5y=28

4x+5y=16

In both equations, there is a 5y. This way, we can cancel them out by subtracting the 2 equations.

4x=12

x=3

Now that we know x, we can plug it back into either equation to find y.

8(3)+5y=28

24+5y=28

5y=4

y=4/5=0.8

Nostrana [21]2 years ago

5 0

Answer:

x=3, y=0.8

Step-by-step explanation:

8x+5y=28

4x+5y=16

Subtract the second simultaneous equation from the first.

You are left with: 4x=12

12/4=3

x=3

Substitute this back into one of the equations.

8(3)+5y=28

8*3=24

28-24=4

4=5y

4/5=0.8

y=0.8

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the boundary of a rectangular farm field in ireland has a straight rock wall along one side and fences along its other three sid

Inessa [10]

Answer:

781250 $ft^{2}$

Step-by-step explanation:

Let y is the length of the farm field

Let x is the width of the farm field

Given that, no fencing is necessary along the rock wall, so we can find the perimeter of the farm is:

2x + y = 2500 feet

<=> y = 2500 -2x

The are of the farm has the following formula:

A = x*y

<=> A = x(2500 - 2x)

<=> A = 2500x -2 $x^{2}$

To have the maximum area of field in square feet, we need to use differentials to estimate:

$\frac{dA}{dx}$ = 2500 - 4x

Set $\frac{dA}{dx}$ = 0, we have:

2500 - 4x = 0

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=> y = 2500 - 2*625 = 1250 feet

So the maximum area of field is:

A = x*y = 625*1250 = 781250 $ft^{2}$

7 0

3 years ago

I need all help possible.

Leviafan [203]

So there are 52 horses
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12:40
12/40

Hope this helps :)

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2 years ago

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snow_lady [41]

Step-by-step explanation:

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2 years ago

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makkiz [27]

Answer:

Step-by-step explanation:

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2 years ago

Read 2 more answers

Writing and Solving an Equation to Find Negative Integers Two negative integers are 5 units apart on the number line, and their

Shtirlitz [24]

Answer:

-23

Step-by-step explanation:

Let first negative integer = x

The second = x +5

Their product = 126, hence,

x * (x +5) = 126

x^2 + 5x = 126

x^2 + 5x - 126 = 0

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x(x + 14) - 9(x+14) =0

(x - 9) = 0 or (x + 14) = 0

x = 9 or x = - 14

Since x is said to be a negative integer,, the our x = - 14

First integer = - 14

Second integer = (x + 5) = (-14 + 5) = - 9

Sum of both integers :

-14 + - 9 = - 23

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2 years ago