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2 years ago

How to solve 3x-y=11, x+2y=6 with the method of elimination?

Mathematics

1 answer:

zubka84 [21]2 years ago

4 0

Answer:

First point we take the centre number

2[ 3x-y=11]

-1[ x+2y=6]

second we multiply and we adding

6x-2y=22

-x+-2y=-6

_________

5x/5=18/5

x= 3.4

Step-by-step explanation:

third point we take 3x-y=11 any x where we see we change 3.4

3(3.4)-y=11

10.2-y=11

y=10.2-11

y=0.8

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What is the coefficient in the expression 5+9 y

damaskus [11]

Answer:

Step-by-step explanation:

because 9 is in front of the variable y

whenever there is a number before a variable then that number is a coefficient

For example:

3x+2x+5x=y

3,2,5 are all coefficients of x

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3 years ago

A boat traveled 147 miles downstream and back. The trip downstream took 7 hours. The trip back took 147 hours. Find the speed of

KonstantinChe [14]

Answer:

The speed of boat in still water is 11 miles per hour

The speed of current is 10 miles per hour .

Step-by-step explanation:

Given as :

The distance cover by boat in downstream = $d_1$ = 147 miles

The time taken by boat in downstream trip = $t_1$ = 7 hours

The distance cover by boat in upstream = $d_2$ = 147 miles

The time taken by boat in upstream trip = $t_2$ = 147 hours

Let The speed of boat in still water = $s_1$ = x mph

And The speed of the current = $s_2$ = y mph

Now, According to question

Speed = $\dfrac{\textrm Distance}{\textrm Time}$

For downstream

$s_1$ + $s_2$ = $\dfrac{d_1}{t_1}$

or, x + y = $\dfrac{147}{7}$

I.e x + y = 21 mph ..........1

For upstream

$s_1$ + $s_2$ = $\dfrac{d_2}{t_2}$

or, x - y = $\dfrac{147}{147}$

I.e x - y = 1 mph ..........2

Now, Solving Eq 1 and 2

I.e (x + y) + (x - y) = 21 + 1

Or, (x + x) + (y - y) = 22

Or, 2 x = 22

∴ x = $\frac{22}{2}$

I.e x = 11 mph

So, speed of boat = x = 11 miles per hour

Again, put The value of x in Eq 2

So, x - y = 1 mph

I.e 11 - y = 1

∴, y = 11 - 1

I.e y = 10 mph

So, speed of current = y = 10 miles per hour

Hence The speed of boat in still water is 11 miles per hour , and The speed of current is 10 miles per hour . Answer

3 0

2 years ago

Solve Tan^2 theta= 1+sec theta

stiv31 [10]

Answer:sec0

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers

Kofi estimated that he would run a total of 10 km in 1 h. In 1 h, he actually ran 46 times around a track 0.25 km long, going a

strojnjashka [21]

The equation to find percent error is

$\frac{actual-theoretical}{theoretical}*100$

where actual is the value that actually came out (in this case, 11.5 km) and theoretical is the value that was supposed to come out (in this case, 10 km). Just plug in the numbers and simplify.

$\frac{actual-theoretical}{theoretical}*100\\\\\frac{11.5-10}{10}*100=\frac{1.5}{10}*100=15\%\ error$

So, the true answer would be 15%. Apparently, the question you're asking takes 11.5 as the theoretical and the 10 as the actual (which I personally disagree with)

If you plugged in the numbers that way, the answer comes out to 13.04%. So, the correct answer for your answer choices is c. 13%

3 0

2 years ago

A point M on a segment with endpoints X (1, −2) and Y (10, 3) partitions the segment in a 5:1 ratio. Find M. You must show all w

quester [9]

The point M is given by coordinates; (8.5, 2.16)

<h3>Ratio coordinate</h3>

The ratio XM : MY is 5:1

Therefore, on the x-axis;

The coordinate of M can be evaluated as follows;

5/1 = (a-1)/(10-a)

By Cross-product;

50 -5a = a -1

51 = 6a

a = 8.5.

Similarly, on the y-axis;

The coordinate of M can be evaluated as follows;

5/1 = (b-(-2))/(3-b)

By Cross-product;

15 -5b = b +2

13 = 6b

b = 2.16.

Ultimately, the coordinate of point M is; (8.5, 2.16)

How to solve 3x-y=11, x+2y=6 with the method of elimination?​

How to solve 3x-y=11, x+2y=6 with the method of elimination?