Solve the system of equations 3y + 2z = 12 and y – z= 9.

1 answer:

3 0

$\left\{\begin{array}{ccc}3y+2z=12\\y-z=9&|multiply\ both\ sides\ by\ 2\end{array}\right\\\underline{+\left\{\begin{array}{ccc}3y+2z=12\\2y-2z=18\end{array}\right}\\.\ \ \ \ 5y=30\ \ \ |divide\ both\ sides\ by\ 5\\.\ \ \ \ y=6\\\\subtitute\ the\ value\ of\ y\ to\ the\ equation\ y-z=9\\\\6-z=9\ \ \ |subtract\ 6\ from\ both\ sides\\-z=3\ \ \ |change\ signs\\z=-3\\\\Answer:\left\{\begin{array}{ccc}y=6\\z=-3\end{array}\right$

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Which fractions are equivalent to 10/12? Select each correct answer. 2/3 5/6 12/24 30/36 50/60 60/84

Yuri [45]

Answer:

[See Below]

Step-by-step explanation:

✦ Turn into decimals:

$\frac{10}{12}=0.83$

$\frac{2}{3} =0.67$

$\frac{5}{6} =0.83$

$\frac{12}{24} =0.5$

$\frac{30}{36} =0.83$

$\frac{50}{60} =0.83$

$\frac{60}{84} =0.71$

So $\frac{10}{12}$ ≈ $\frac{5}{6},\frac{30}{36},and,\frac{50}{60}$ .

~<em>Hope this helps Mate. If you need anything feel free to message me. </em>

4 0

3 years ago

Help me please this is due in 3 hour's

makkiz [27]

485, because the mean means you need to calculate the average. to find the average, you take the smallest number from the data set and the largest number. add the largest number by the smallest number and divide by the set of numbers you added (2). Example: (720+250=970 divided by 2 =485)

6 0

2 years ago

Elena's aunt bought her a $150 savings bond when she was born. When Elena is 20 years old, the bond will have earned 105% in int

const2013 [10]

The worth of the bond is $307.50.

<h3>What is the worth of the bond?</h3>

The worth of the bond is the sum of the bond when it was bought and the interest earned on the bond.

Worth of the bond = interest rate + value when the bond was bought

Interest = 105% x $150

1.05 x $150 = $157.70

Worth of the bond = $157.70 + $150 = $307.50

To learn more about interest, please check: brainly.com/question/26164549