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3 years ago

Can y'all please help.

Mathematics

1 answer:

sattari [20]3 years ago

6 0

Answer:

See explanation

Step-by-step explanation:

<u>Step 1.</u> Substitute for d to solve for n:

From the first equation:

$d=70-n$

Then substitute it into the second equation:

$0.1(70-n)+0.05n=5.5\\ \\7-0.1n+0.05n=5.5\\ \\7+(-0.05n)=5.5\\ \\-0.05n=5.5-7=-1.5\\ \\n=\dfrac{-1.5}{-0.05}=30$

<u>Step 2:</u> Substitute for n to solve for d:

$d+n=70\\ \\d+30=70\\ \\d=70-30=40$

There are 40 dimes and 30 nikels in the piggy bank

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If a triangular road sign has a center height of

Paladinen [302]

Answer:

Formula

A = 1/2 b * h

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(2x + 15)(x - 8) = 0

Solve for x

2x + 15 = 0

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x = - 7.5 a negative measurement is useless. Discard this answer.

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3 0

2 years ago

Please answer this ASAP

valkas [14]

Answer:

x = 2

Step-by-step explanation:

First, let's write out our equation:

$2x-4=6-3x$

I want to isolate x on one side, so first, I'll add 4 to both sides to remove the -4 from next to 2x:

$2x-4+4=6-3x+4\\2x=-3x + 10$

Notice that I combined like terms with the -4 and 4 (to get 0) and the 6 and 4 on the right side (to get 10). Next, I'll add 3x to both sides:

$2x + 3x = -3x + 3x + 10$

And then I'll add like terms:

$5x=10$

Now, all we have to do is divide both sides by 5:

$5x/5=10/5\\x=2$

And there's our answer. Hopefully that's helpful! :)

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2 years ago

Al obtener el valor de lo que costará la fiesta de graduación para tu grupo te das cuenta que el lugar que decidieron alquilar p

dybincka [34]

Explicación paso a paso:

Debemos buscar el costo de cada boleto y la cantidad de personas que deben ir.

Dada la función que da forma al comportamiento expresado como;

f (x) = (-2x) ^ 2 + 80x + 300 donde;

x es el costo de cada boleto

f (x) es el número de personas que deben ir

Para obtener x, usaremos la expresión;

x = -b / 2a

De la ecuación cuadrática dada, a = -2, b = 80 yc = 300

Sustituir;

x = -80/2 (-2)

x = -80 / -4

x = 80/4

x = 20

Por lo tanto, el boleto cuesta $ 20.

Lo siguiente es obtener la cantidad de personas que deben ir. Para conseguirlo, sustituiremos x = 20 en la expresión modelada como se muestra;

f (x) = (-2x) ^ 2 + 80x + 300

f (20) = (-2 (20)) ^ 2 + 80 (20) +300

f (20) = (-40) ^ 2 + 1600 + 300

f (20) = 1600 + 1600 + 300

f (20) = 3500

Por lo tanto, 3500 personas tienen que ir

8 0

3 years ago

Six years after a tree was planted, its height was 7 feet. Nine years after it was planted, its height was 16 feet. Which of the

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Considering that the grows at a constant rate we can form an equation where x = how many years after it was planted
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Now we just need to find how many feet it grows each year. To do that we just need to compare its height from a certain age to another:
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so x=6 and y = 7

9 years after it was planted: 16 feet
so x= 9 y=16

With thay we can conclude that in 3 years , the tree grew 9 feet. To discover how much the tree grow each year we just nee to divide 9 feet by 3 years which is 3 feet every year.

To write the equatopn now we just need to find the y-intercept which we can discover by setting x to 0:
If in 6 years after the tree was planted it is 7 feet long , we can discover how long it was when it was planted by subtracting 6 years of growth (The slope ) which is 3
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7 - 18 = -11
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( I know it doesnt make sense , but if you apply to a graph it will make more sense )

Now we can make the equation
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2 years ago