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andrew-mc [135]
3 years ago
15

A submarine cruises underwater at 20 km/h and on

Mathematics
1 answer:
Darina [25.2K]3 years ago
4 0

Answer:

System of equations:

20x + 30y = 650

x + y = 25

Time underwater = 10 hours

Time at the surface = 15 hours

Step-by-step explanation:

Let x = time underwater at 20 km/h.

Let y = time on the surface at 30 km/h.

speed = distance/time

distance = speed * time

distance underwater: 20x

distance on the surface: 30y

total distance: 650

20x + 30y = 650

total time: x + y

total time: 25

x + y = 25

20x + 30y = 650

x + y = 25

20x + 30y = 650

-20x - 20y = -500

--------------------------------

          10y = 150

              y = 15

x + y = 25

x + 15 = 25

x = 10

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Answer:

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Step-by-step explanation:

Given: Discount- 40% off on original price.

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Lets assume the original price be "x".

We know there is 40% on original price and Perry uses $25 gift card.

Remember; Total cost= Original\ price- discount- gift\ card

Now, finding the original price of Iphone.

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⇒ 0.60x-25= 334.40

Adding both side by 25

⇒0.60x= 334.40+25

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5 0
3 years ago
Which expression can be used to find the surface area of the following square pyramid
mariarad [96]

Answer:

a. 36+15+15+15+15

Step-by-step explanation:

The base of the pyramid is a square. We know that all sides of a square are equal so if we multiply the two sides of the base square(6*6) we get 36.

The area of a triangle can be found with the formula (b*h)/2. If we input the given values of 5 and 6 into our equation, then (5*6)/2 is 15 and since there are 4 triangles in the square pyramid, you multiply 15 by 4 (or add 15+15+15+15), and add the 36 from the base square.

Hope this helps :)

5 0
3 years ago
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Can someone help me with these both
Anna [14]
Hello,
so all you have to do is match the abbreviations to the triangles. The abbreviations stand for what is the SAME in both triangles, denoted by similar markings on equal sides and angles.

Abbreviations:
SSS = Side-Side-Side
SAS = Side-Angle-Side
ASA = Angle-Side-Angle
AAS = Angle-Angle-Side
HL = Hypotenuse-Leg

* Note - the angle side angle must go around the triangle in that order. ASA has the side BETWEEN the congruent angles.. SSA does NOT work.

(9.) ASA
(10.) AAS
(11.) SSS
(12.) No way to tell if congruent. (only 3 angles no side)
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(14.) SAS
(15.) HL

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3 years ago
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o-na [289]

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Step-by-step explanation:

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2 years ago
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Answer:

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