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4 years ago

Using the linear combination method what is the solution to the system of linear equations 7x - 2y = -20 and 9x + 4y = -6

1 answer:

8 0

x should equal -2 and y should equal -3 to solve this i multiplied the first equation by 2 then got rid of the 4y and -4y then i added the 14x to the 9 equaling 23x and added the -40 to the -6 which became 23x=-46 i solved this getting -s for x, then i plugged that into the equations to get y which was -3

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Help What is an equation of the line that passes through the points (-4, 4) and (8.1)?

Svetach [21]

Answer:

y = -1/4x +3

Step-by-step explanation:

Hope this helps!

3 0

3 years ago

How long does it take an SR-71 Blackbird to make a surveillance run of 10,026 miles if it travels at an average of 2,228 mph

g100num [7]

This is simple division:
$t = \frac{10026}{2228}$

So, plug it into your calculator and you get:
$t = 4.5$

Your answer's that it takes 4.5 hrs for the surveillance run.

4 0

3 years ago

21 is 30% of what number?

WARRIOR [948]

Answer:

21 is 30% of 70

Explanation:

We know that 100% is the original number.

Equation:

(21/30)*100

21/3 * 10

7 * 10

70 ....this is the answer, original number.

5 0

2 years ago

Read 2 more answers

A 20 foot ladder leaning against a wall is used to reach a window that is 17 feet above the ground. How far from the wall is the

Liono4ka [1.6K]

Answer:

The wall is 10.5 foot far from the bottom of the ladder.

Step-by-step explanation:

Given:

Height of the ladder leaning against wall (Hypotenuse) = 20 foot.

Height from where the window is above from the ground (Leg1) = 17 feet.

To find the distance of the bottom of the ladder far from the wall (Leg2) = ?

Now, by using the pythagorean theorem:

$Hypotenuse^{2} = (Leg1)^{2} + (Leg2)^{2}$

$20^{2} =17^{2}+(Leg2) ^{2}$

$400=289+(Leg2)^{2}$

$400-289=(Leg2)^{2}$

$111=(Leg2)^{2}$

by squaring both sides

$Leg2=10.535$

10.535 foot rounded nearest tenth is 10.5 foot.

Therefore, the wall is 10.5 foot far from the bottom of the ladder.

6 0

3 years ago

If an experimenter sets equal to .01, then she is defining a "statistically rare" event as an event occurring more than one time

Fynjy0 [20]

Answer:

The correct answer is an event occurring one or fewer times in 100 times if the null hypothesis is true.

Step-by-step explanation:

For a statistically rare event, its probability is relatively small and the event is very unlikely to occur. Therefore, if an experimental sets equal to 0.01 which is statistically rare, then we can interpret this mathematically as:

p(event) = 0.01 = 1/100

where p(event) is the probability of the event.

In addition, statistically, null hypothesis signifies no major difference between the specified parameters, and any obvious difference that might occur as a result of experimental error. Thus, it can be concluded that the event is occurring one or fewer times in 100 times if the null hypothesis is true.

3 0

4 years ago