Find the price per ounce rounded to the nearest cent: 1 lb 10 oz for $10.98.

What is the value of y in this system of equations: 3x + y = 9 y = –4x + 10 ?

Ahat [919]

3x + y = 9 (I)
y = –4x + 10 (II)
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 $\left \{ {{3x + y = 9 } \atop {y = -4x + 10 }} \right.$

Pass the incognito "4x" to the first term, changing the signal when changing sides.
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simplify by (-1)
 $\left \{ {{3x + y = 9.(-1)} \atop {4x + y = 10 }} \right.$ 

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 $\left \{ {{- 3x - \diagup\!\!\!\!y =-9} \atop {4x + \diagup\!\!\!\!y = 10}} \right. 
$

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 $\left \{ {{- 3x = - 9} \atop {4x = 10}} \right.$ 

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 $\boxed{x = 1}$ 

Substitute in equation (I) to find the value of "Y".

3x + y = 9 (I)
3*(1) + y = 9
3 + y = 9
y = 9 - 3
$\boxed{y = 6}$

Answer:
$\boxed{\boxed{ \left \ {{x=1} \atop {y=6}} \right. }}$

6 0

2 years ago

Help solve this I’m not sure if my answer was right. Pythagorean theorem.

Ganezh [65]

Answer:

C. since 8, 15, 17 are pythagorean triples

8 0

2 years ago

How to solve <img src="https://tex.z-dn.net/?f=log_%7By%7D%285y%29%20%3D%202" id="TexFormula1" title="log_{y}(5y) = 2" alt="log_

Natalija [7]

Answer:

y = 5

Step-by-step explanation:

Expand the logarithm:

$\log_y{(5)}+\log_y{(y)}=2\\\\\dfrac{\log{(5)}}{\log{(y)}}+1=2 \quad\text{change of base formula}\\\\\dfrac{\log{(5)}}{\log{(y)}}=1 \quad\text{subtract 1}\\\\\log{(5)}=\log{(y)} \quad\text{multiply by log(y)}\\\\5=y \quad\text{take the anti-log}$

_____

You can also take the antilog first:

5y = y²

y(y -5) = 0 . . . . . subtract 5y, factor

y = 0 or 5 . . . . . y=0 is not a viable solution, so y=5.

5 0

3 years ago

During an algebra class a teacher asked for examples of non-prime numbers. Jake says 51, Teresa says 41, and let Liu says 21. Wh

USPshnik [31]

The students that are correct are Jake , and Liu because 51, and 21 are composite.

Hope this helps!

3 0

2 years ago

Read 2 more answers

The average age of all students at a certain college is 22 years and the standard deviation is 2 years. What is the probability

Marianna [84]

Answer:

The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159

Step-by-step explanation:

According to the given data we have the following:

mean = μ= 22

standard deviation = σ = 2

n = 100

μx = 22

σx=σ/√n=2/√100=0.2

Therefore, P( x < 21.8)=P(x-μx)/σx<(21.8-22)/0.2

=P(z<-1)

= 0.159

The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159

3 0

3 years ago