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3 years ago

4x - 2y =8 X - 3y = - 3 Solve the simultaneous equation with workings please

1 answer:

6 0

Okay, (Assuming this is workings, dunno if it's the right method) multiply the bottom equation by -4 (for simplicity's sake here) so you get -4x+12y=12. (Changing the signs here) then to get rid of the x in the equation, add the two together.
4x-2y=8
+
-4x+12y=12
=
10y=20
Divide 20 by 10 to get y=2. then put the answer for y back into one of the equations.
x- 3(2)=-3
x-6=-3
x=3
in sum, y=2 and x=3.
That is how it's done, hope it helps:)

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What is the ratio 28 : 4 in it's simplest form?

Lisa [10]

Answer:

7:1

Step-by-step explanation:

28:4=

7(4):1(4)=

7:1

Hope this helps!

5 0

3 years ago

Read 2 more answers

What is 4,328.12 in expanded form?

shepuryov [24]

Hope this helps

Answer = 4,328.12
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4 0

3 years ago

The length (in centimeters) of a typical Pacific halibut t years old is approximately f(t) = 200(1 − 0.956e−0.18t). Suppose a Pa

horsena [70]

Answer:

7.2 years

Step-by-step explanation:

$f(t) =200(1 - 0.956e^{-0.18t})$

where f(t) is the length and t is the number of years old

given the Mike measures 148 cm, we need to find out the age

So we plug in 148 for f(t) and solve for t

$148 =200(1 - 0.956e^{-0.18t})$

divide both sides by 200

$\frac{148}{200} = 1 - 0.956e^{-0.18t}$

Now subtract 1 from both sides

$-0.26= - 0.956e^{-0.18t}$

Divide both sides by -0.956

$\frac{0.26}{0.956} =e^{-0.18t}$

Now take ln on both sides

$\frac{0.26}{0.956} =e^{-0.18t}$

$ln(\frac{0.26}{0.956} )=-0.18tln(e)$

$ln(\frac{0.26}{0.956} )=-0.18t$

divide both sides by -0.18

t=7.2

So 7.2 years

5 0

3 years ago

As part of a study done for a large corporation, psychologists asked randomly selected employees to solve a collection of simple

zhenek [66]

Answer:

$P(A')=1-0.411=0.589$

And that represent the probability that they take longer than 7 minutes to solve the puzzles.

Step-by-step explanation:

The complement rule is a theorem that provides a connection between the probability of an event and the probability of the complement of the event. Lat A the event of interest and A' the complement. The rule is defined by: $P(A)+P(A') =1$

On this case we have that n= 56 represent the employees selected to solve the puzzles.

We know that 23 out of the 56 selected solved the puzzles in less than 7 minutes.

Let's define the events A and A' like this:

A: Employees solved puzzles in less than 7 minutes

By the complement rule then:

A' : Employees solved puzzles in more than 7 minutes

Based on this we are interested to find the probability for A'

We can begin finding P(A), from the definition of probability we know:

$P(A)=\frac{Possible outcomes}{Total outcomes}$

For this case if we replace we got:

$P(A) =\frac{23}{56}=0.411$

And using the complemnt rule we got:

$0.411 +P(A')=1$

And solving for P(A') we got:

$P(A')=1-0.411=0.589$

And that represent the probability that they take longer than 7 minutes to solve the puzzles.

4 0

3 years ago

Please help!!!

Leto [7]

Answer:

- The scientist can use these two measurements to calculate the distance between the Sun and the shooting star by applying one of the trigonometric functions: Cosine of an angle.

- The scientist can substitute these measurements into $cos\alpha=\frac{adjacent}{hypotenuse}$ and solve for the distance between the Sun and the shooting star (which would be the hypotenuse of the righ triangle).

Step-by-step explanation:

You can observe in the figure attached that "AC" is the distance between the Sun and the shooting star.

Knowing the distance between the Earth and the Sun "y" and the angle x°, the scientist can use only these two measurements to calculate the distance between the Sun and the shooting star by applying one of the trigonometric functions: Cosine of an angle.

This is:

$cos\alpha=\frac{adjacent}{hypotenuse}$

In this case:

$\alpha=x\°\\\\adjacent=BC=y\\\\hypotenuse=AC$

Therefore, the scientist can substitute these measurements into $cos\alpha=\frac{adjacent}{hypotenuse}$ , and solve for the distance between the Sun and the shooting star "AC":

$cos(x\°)=\frac{y}{AC}$

$AC=\frac{y}{cos(x\°)}$

3 0

3 years ago

Read 2 more answers