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3 years ago

Determine the solution to the system of equations {4x+15y=40

Mathematics

1 answer:

oee [108]3 years ago

8 0

Step-by-step explanation:

4x+15y= 40-5y= 20

= 4x+15y+5y= 40-20

4x+20y= 20

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Find the varible for 6-2x=6x-10x+18

masha68 [24]

Answer:

x=6

Step-by-step explanation:

3 0

3 years ago

a motorboat traveling with a current can go 160km in 4 hours. against the current it takes 5 hours to go the same distance. find

irakobra [83]

The speed of motorboat is 36 kmph and speed of current is 4 kmph.

Step-by-step explanation:

Distance covered in 4 hours = 160 km

Time took on return trip = 5 hours

Let,

x represent the speed of boat.

y represent the speed of current.

Combined speed of boat and current when in same direction = x+y

Speed of boat and current when travelling against = x-y

Distance = Speed * Time

Speed = $\frac{Distance}{Time}$

x+y = $\frac{160}{4}$

x+y = 40 Eqn 1

x-y = $\frac{160}{5}$

x-y = 32 Eqn 2

Adding Eqn 1 and Eqn 2

$(x+y)+(x-y)=40+32\\x+y+x-y=72\\2x=72$

Dividing both sides by 2

$\frac{2x}{2}=\frac{72}{2}\\x=36$

Putting x=36 in Eqn 1

$36+y=40\\y=40-36\\y=4$

The speed of motorboat is 36 kmph and speed of current is 4 kmph.

Keywords: linear equation, addition

Learn more about linear equations at:

#LearnwithBrainly

8 0

3 years ago

a bicycle wheel has a diameter of 40 cm how many revolutions would a wheel make if the bike travels 1 km pi=3.14 (answer please

andriy [413]

Circumference of a circle = Diameter × pi
Circumference of a circle = 40 cm × 3.14
Circumference of the wheel = 125.6 cm

1 Km = 1000m
Circumference of the wheel × 1000m = The number of revolutions
125.6 × 1000m = 125600

The wheel would make 125600 revolutions if the bike travels 1 km.

3 0

3 years ago

What is the area of the rectangle below? 9 feet 7 feet

barxatty [35]

Answer:

63 feet ^2

Step-by-step explanation:

Well assuming your presented with length and width.

9*7=63

5 0

3 years ago

Find the distance between the two points rounding to the nearest tenth (if necessary).

Evgesh-ka [11]

Answer:

approximately 8.5

Step-by-step explanation:

So you can use the distance formula: $\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}\\$ which is derived from the Pythagorean theorem because normally x2-x1 would kind of give the distance length between x2 and x1 except sometimes it would be negative which wouldn't make much sense right? but it doesn't matter because it's being squared so the value ultimately becomes positive, and the same thing goes for the y-value. the distance between x2 - x1 really represents the base and y2-y1 represents the height and then adding them together gives the hypotenuse squared which is why you take the square root over the entire thing to find the distance, since the hypotenuse is the shortest distance between two points

Now all you have to do is plug the values in to get

$\sqrt{(-7 - (-4))^2 + (-8 - 0)^2}\\\sqrt{(-3)^2 + (-8)^2}\\\sqrt{9 + 64}\\\sqrt{73}\\distance \approx 8.5$

5 0

2 years ago