Which expression is equivalent to 5(2+7)?

Please Help! Show all the steps!

likoan [24]

You can start by subtracting different equations from each other.

3x + 2y + 3z = 1

subtract

3x + 2y + z = 7

2z = -6

divide by 2

z = -3

add the following two expressions together:

3x + 2y + z = 7

3x + 2y + 3z =1

6x + 4y + 4z = 8

subtract the following two expressions:

6x + 4y + 4z = 8

5x + 5y + 4z = 3

x - y = 5

^multiply the whole equation above by 3

3x - 3y = 15

subtract the following two expressions:

3x - 3y = 15

3x + 2y = 10

-5y = 5

divide each side by -5

y=-1

take the following expression from earlier:

x - y = 5

substitute y value into above equation

x - - 1 = 5

2 negatives make a positive

x + 1 = 5

subtract 1 from each side

x = 4

Therefore x = 4, y = -1, z = -3

I checked these with all 3 equations and they worked :)

(it's quite complicated, comment if you don't understand anything) :)

7 0

3 years ago

The radius of a circle with area A can be approximated using the formula r = the square root of A/3 . Estimate the radius of a w

Arturiano [62]

Answer: 12

Step-by-step explanation:

Given:

A = 452

r = √A/3

Step 1: Substitute 452sqf for A

r = √452/3

Step 2: Solve

452 ÷ 3 = 150.66∞

√150.66∞ = 12.27∞

12.27∞ rounded to the nearest integer equal 12

3 0

3 years ago

Find the common fraction equivalent to 0.12

jonny [76]

The answer is: " $\frac{4}{33}$ "  .
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Given: 0.1212121212..... repeating ; write that value as a fraction;
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In other words; we are given: "0.1212121212..... repeating infinitely" ;

→ that is to say; "0.12 ... ; {the "12" decimal portion repeats infinitely} ;
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→ We write this value, as a fraction, as: "12/99" ;
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→Explanation:
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Note: "0.99999999...... repeating infinitely; = "1" .
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→Since:

Let us say that we have:

"x = 0.999999 ; repeating infinitely;

In order words, let us say we have: "x = 0.9.... ; the "9" decimal repeats infinitely;
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Then "10x" ; (that is: "10" multlipled by "x"; or "10*x" or "10x" ); is equal to:

"10" * (0.999999.....) = 9.99999999...... (the "9" decimal repeats infinitely);

in other words: 10x = 9.99999999....

Divide each side by "10" ;

to get "x = 0.9999999....." ; the decimal "9" repeats indefinitely...." ;

But if you have: "10x = 10" ; divide each side of the equation by "10" ;
you get: "x = 1" .
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Also, if "x = 0.9999...(repeating infinitely);

then: 10x = 9.99999.
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10x = 9.999999999999999......
−   x = 0.999999999999999.......
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9x = 9.00000000000000000000.....

→ 9x = 9 ;

Divide each side of the equation; to get;

9x /9 = 9/ 9 ; to get: x = 1 ; and we have: x = 0.9999.... ; so
x= 0.99999.... = 1 ;
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So, if the numbers "12" is repeating, we divie "12" by "99" ;
that is; we divide "12" by "two 9's" ; since "12" is a "TWO-digit number"; a "two-digit number" is being repeated infinitely.
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So; 0.12121212.....(the "12" is the decimal that repeats infinitely);

= 12/99 ; which can be simplified;

Divide each side (both the numerator AND the denominator); by "3" ;
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" 12/99 " = "(12÷3) / (99÷3) = 4/33 " .
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The answer is: $\frac{4}{33}$   .
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8 0

3 years ago

Read 2 more answers

PROBABILITY. Areas of regions: Entire Target=84in^2, Red area=28in^2, Green area=7in^2, Yellow area=9.42in^2, Blue area=39.58in^

abruzzese [7]

Answer:

HIIIIIIIIIIIIIIIIIIIIIIIIII

Step-by-step explanation:

8 0

3 years ago

What is the inequality pls help

Colt1911 [192]