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3 years ago

Solve using the substitution method.

Mathematics

1 answer:

Brilliant_brown [7]3 years ago

5 0

Answer:

x = 1, y = 4

Step-by-step explanation:

This is very simple

Since you have 2 equations with the same coefficient of x, just minus one equation from another:

x + 3y = 13

x + 2y = 9

1y = 4

Sub y = 4 into any of the 2 equation,

x + 3(4) = 13

x + 12 = 13

x = 13 - 12

= 1

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Which graph does not represent a function

Marysya12 [62]

Answer:

Graph D

Step-by-step explanation:

it does not pass the linear test to qualify as a function

3 0

4 years ago

Read 2 more answers

Recall the question for a circle with center. (H,k) and Radius r. At what point in the first quadrant does the line with equatio

kap26 [50]

Answer:

the point lies at (1.7, 3.6) in the first quadrant.

Step-by-step explanation:

The formula for a circle with centre (h,k) and radius (r) can be expressed as :

(x-h)² + (y-k)² = r²

Now for the expression of the circle with radius 3 and center (0,1), we have:

(x - 0)² + (y - 1)² = 3²

x² + (y-1)² = 9

replacing y = 1.5x + 1 in the above equation, we have:

x² + (( 1.5x + 1 ) - 1 )² = 9

x² + ( 1.5x +1 - 1)² = 9

x² + (1.5x)² = 9

x² + 2.25x² = 9

3.25x² = 9

x² = 9/3.25

$x^2 = \dfrac{9}{\dfrac{13}{4}}$

$x^2 = {9} \times {\dfrac{4}{13}}$

$x= \sqrt{{9} \times {\dfrac{4}{13}}}$

$x= \pm 3 \times \dfrac{2}{\sqrt{13}}}$

$x= \pm \dfrac{6}{\sqrt{13}}}$

x = 1.7 in the positive x - axis

Recall that:

y = 1.5x + 1

y = 1.5 (1.7) +1

y = 2.55 +1

y = 3.55

y = 3.6

Therefore, the point lies at (1.7, 3.6) in the first quadrant.

4 0

3 years ago

Water is being pumped to empty a swimming pool.

IceJOKER [234]

To empty the pool, you need to lower the water level by 150cm. since you can only lower it by 30cm every 2 hours (also same as 15 cm per hour), that means it will take you 10 hours.

150cm*(2 hours)/(30cm) = 150*(1/15) = 150/15 = 10.

6 a.m. + 10 hours = 4 p.m.

So the answer is C.) 4 p.m.

3 0

4 years ago

Please Help I will Give Brainest and 100 points and no fake answers

Lady bird [3.3K]

Step-by-step explanation:

$\sqrt{3} is \: between1.7and1.8$

7 0

3 years ago

A bottler of drinking water fills plastic bottles with a mean volume of 1,000 milliliters (mL) and standard deviation The fill v

trapecia [35]

Answer:

84.13% of bottles will have volume greater than 994 mL

Step-by-step explanation:

Mean volume = u = 1000

Standard deviation = $\sigma$ = 6

We need to find the proportion of bottles with volume greater than 994. So our test value is 994. i.e.

x = 994

Since the data is normally distributed we will use the concept of z-score to find the required proportion. First we convert 994 to its equivalent z-score, then using the z-table we will find the corresponding value of proportion. The formula to calculate the z score is:

$z=\frac{x-u}{\sigma}$

Substituting the values, we get:

$z=\frac{994-1000}{6}=-1$

This means 994 is equivalent to a z score of -1. Now we will find the proportion of z values which are greater than -1 from the z table.

i.e. P(z > -1)

From the z-table this value comes out to be:

P(z >- 1) = 1 - P(z < -1) = 1 - 0.1587 = 0.8413

Since, 994 is equivalent to a z score of -1, we can write that proportion of values which will be greater than 994 would be:

P( X > 994 ) = P( z > -1 ) = 0.8413 = 84.13%

4 0

3 years ago