Answer:
I believe that this is the best answer mark brainliest if it is
Step-by-step explanation:
The square root property should have been applied to both complete sides of the equation instead of to select
variables.
Answer:
13 is the number.
Step-by-step explanation:
Given:
Twice the difference of a number and 9 equals 8.
Let the unknown number be 'x'.
Therefore, as per question:
The difference of 'x' and 9 = 
Twice the difference means 2 times the difference. So, we multiply 2 to the difference. Therefore,

Now, the above expression is equal to 8. So, we equate the above expression to 8. This gives,

Solving for 'x', we get:
Using distributive property of addition and distributing 2 inside the bracket. This gives,

Therefore, the unknown number is 13.
Now, we can verify our answer.

Therefore, the answer is correct.
Answer:
Postulate.
Step-by-step explanation:
Postulate is a statement, also known as an axiom, which is taken to be true without proof.
Answer: Since the dependent variable is the height in cm, and the independent variable is the color of light, then a testable question could be "Will the color of a lamp affect the height of plants?"
Answer:
Step-by-step explanation:
hello :
12x^3-9x²-4x+3= 3x²(4x-3)-(4x-3)