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3 years ago

Which statement correctly explains how Mari could find the solution to the following system of linear equations using

Mathematics

1 answer:

just olya [345]3 years ago

7 0

Multiply the first equation by 7 and the second equation by 2, and then add.

Step-by-step explanation:

2f - 5g=-9

-7f + 3g=4

To eliminate any variable , we need to make the coefficients same with different sign and add it

the coefficient of 'f' in first equation is 2

the coefficient of 'f' in second equation is -7

We already have different sign so we make the coefficients same

To make the coefficient same , we multiply the first equation by 7 and second equation by 2

So equation becomes

14f - 35g = -63

-14f + 6g = 8

Now when we add both equations, 'f' gets cancelled

-29g = -55

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Solve the following by elimination method <br> 11x+15y+23=0 and 7x-2y-20=0

mr Goodwill [35]

Let 11x + 15y + 23 = 0 be equation (1)
And 7x - 2y - 20 = 0 be equation (2)

Multiply equation (1) by 2:
22x + 30y + 46 = 0

Multiply equation (2) by 15:
105x - 30y - 300 = 0

Add equations (1) and (2):
22x + 105x + 30y - 30y + 46 - 300 = 0
127x - 254 = 0
127x = 254
x = 254/127
[x = 2]

Substitute x = 2 in equation (1) to find y:
11(2) + 15y + 23 = 0
22 + 15y + 23 = 0
15y + 45 = 0
15y = -45
y = -45/15
y = -3

Therefore, x = 2 and y = -3.

7 0

3 years ago

What is the value of y?

andrew11 [14]

The value of y is c

7 0

3 years ago

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Which of the following best describes the English expression five more than the quantity of a number minus six?

klasskru [66]

5 + x - 6 hopes this helps

8 0

3 years ago

Ok I’ll ask again cuz one of them said tomorrow and I should watch Jojo something lol so here’s the question shall I k^^* myself

tatuchka [14]

Answer:

never:)

Step-by-step explanation:

5 0

3 years ago

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Ryan is rowing a small boat out to and back from an island 20 miles away at a rate of

Misha Larkins [42]

Answer:

The speed with which Ryan was rowing was 4 mph

Step-by-step explanation:

With a small boat, Ryan wants to row towards an island and come back at a speed of x mph and the island is 20 miles away from him.

Therefore, total 20 + 20 = 40 miles he rowed for 5 hours.

On the way to the island, there was a wind of 4 mph in the direction of his motion and on the way back also there was a wind of 4 mph in the direction of his motion.

So, in the total journey, he has a speed of (x + 4) mph.

Therefore, $\frac{40}{5} = x + 4$

⇒ x + 4 = 8

⇒ x = 4 mph.

Therefore, the speed with which Ryan was rowing was 4 mph. (Answer)

4 0

3 years ago