The answer is –7/26 (in decimal form –0.2692307)
Answer:
<u>The correct answer is A. - 11 square root of 7.</u>
Step-by-step explanation:
We have the expression 2 √28 - 5 √ 63 and we have to find and equal expression.
Let's simplify it:
2 √28 - 5 √ 63
2 √7 * 4 - 5 √ 9 * 7 (28 is also equal to 7 * 4 and 63 is equal to 9 * 7)
2 * 2 √7 - 5 * 3 √ 7
4 √7 - 15 √7
- 11 √7
<u>The equal expression is A. - 11 square root of 7.</u>
Answer:
What are the options?
Step-by-step explanation:
The system of equation that could have led to the equation 9x = 27 is
7x - 2y = 15
x + y = 6
The correct option is the third option
7x - 2y = 15
x + y = 6
<h3>Solving systems of equations</h3>
From the question, we are to determine the system that could have led to 9x = 27
1.
9x + 2y = 21
-9x - 2y = 21
Subtracting, we get
9x + 2y = 21
-9x - 2y = 21
-------------------
18x + 4y = 0
2.
10x - y = 15
x + y = - 12
Subtracting, we get
10x - y = 15
x + y = - 12
---------------------
9x -2y = 27
3.
7x - 2y = 15
x + y = 6
Here, multiply the second equation by 2
2 × [x + y = 6]
2x + 2y = 12
Now, add to the first equation
7x - 2y = 15
2x + 2y = 12
------------------
9x = 27
4.
4x + 3y = 24
-5x - 3y = 3
Subtracting, we get
4x + 3y = 24
-5x - 3y = 3
---------------------
9x + 6y = 21
Hence, the system of equation that could have led to the equation 9x = 27 is
7x - 2y = 15
x + y = 6
The correct option is the third option
7x - 2y = 15
x + y = 6
Learn more on Systems of equations here: brainly.com/question/12691830
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