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3 years ago

If 3x + 9y = 21 , find the value of 4(x + 3y)

Mathematics

1 answer:

mr Goodwill [35]3 years ago

7 0

Answer:

Step-by-step explanation:

The method that should be used is substitution:

Do this by taking 3x+9y=21 and transforming it to be $y=-\frac{1}{2} x+\frac{7}{3}$

Once you have this, substitute the value of y that we just found into 3x+9y=21 to find the value of x: $3x+9(-\frac{1}{2} +\frac{7}{3} ) =21$

Solve for x. You should get 1.5

Once you have this, Plug in 1.5 for the value of x into the y= equation that we found in the beginning: $y=-\frac{1}{2} (1.5)+\frac{7}{3}$

Solve for y. You should get 1.583 (19/12)

Plug in the values of x and y that we found into the last equation to find its value: 4(1.5+3(1.583))

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Which of the following is a correct interpretation of the expression -4 + 13−4+13minus, 4, plus, 13?

7nadin3 [17]

Answer:

Step-by-step explanation:

-4 + 13 - 4 + 13 - 4 + 13

9 - 4 + 13 - 4 + 13

5 + 13 - 4 + 13

18 - 4 + 13

14 + 13

6 0

3 years ago

Write the expression: the sum of the quantity h and 3 divided by 6.

gizmo_the_mogwai [7]

Answer is C because it’s asking for the sum of h and 3 which is then divided by 6

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3 years ago

What is the value of x to the nearest tenth

marishachu [46]

You will have to use trig to solve this:

The side you have is adjacent to the known angle

The side you are looking for is opposite the known angle

^^^This means you need to use tan:

tan(24) = $\frac{x}{12}$

.445222 = $\frac{x}{12}$

^^^input tan(24) into calculator, then multiply 12 to both sides to isolate and solve for x

5.3 ≈ x

Hope this helped!

4 0

3 years ago

— 2y – Зу +8 = 8 — 5у – 12

jasenka [17]

Answer:

No Solution.

Step-by-step explanation:

Equality equation:

— 2y – Зу +8 = 8 — 5у – 12 (Given)

-5y + 8 = -4 - 5y (distributive property of equality)

-5y = -12 - 5y (subtraction property of equality)

= -12 (addition property of equality)

when you add 5y on both sides it cancels the 5y out, it's no solution.

Ace-The Kid Laroi

6 0

2 years ago

How can I create a word problem with the following expressions 15+2d 200-4m

Alenkasestr [34]

For the first expression
15 + 2d
A possible word problem would be this:
A person saves $2 per day of money. Before he started saving, he had $15 dollars set aside. Look for the expression that expresses the total amount of money saved in terms of the number of days passed

The second expression is
200 - 2m
A possible word problem would be this:
The distance from school to the park is 200m. A kid riding a bike is traveling at a speed of 2m/s from the school to the park. Write an expression for the distance remaining between the park and the kid.

6 0

3 years ago