Answer:given below
Step-by-step explanation:
sqrt x^2 +81= x + 10
x^2 + 81 = (x+10)^2
x^2 + 81 = x^2 + 20x + 100
so answer is:  
x^2 + 81 = x^2 +20x + 100
..HOPE IT HELPS YOU...ALL THE BEST
 
        
             
        
        
        
Answer:x = -1.5
Step-by-step explanation:
Simplifying
7x + -9x = 3
Combine like terms: 7x + -9x = -2x
-2x = 3
Solving
-2x = 3
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Divide each side by '-2'.
x = -1.5
Simplifying
x = -1.5
 
        
             
        
        
        
Given:
Expression is

To prove:
If r is any rational number, then  is rational.
 is rational. 
Step-by-step explanation:
Property 1: Every integer is a rational number. It is Theorem 4.3.1. 
Property 2: The sum of any two rational numbers is rational. It is Theorem 4.3.2.
Property 3: The product of any two rational numbers is rational. It is Exercise 15 in Section 4.3.  
Let r be any rational number.
We have,

It can be written as

Now, 
3, -2 and 4 are rational numbers by property 1.
 is rational by Property 3.
 is rational by Property 3.
 are rational by Property 3.
 are rational by Property 3.
 is rational by property 2.
 is rational by property 2.
So,  is rational.
 is rational.
Hence proved.
 
        
             
        
        
        
Answer:
x = 3, 5
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtract Property of Equality
<u>Algebra I</u>
- Terms/Coefficients/Degrees
- Standard Form: ax² + bx + c = 0
- Multiple Roots
- Factoring
- Completing the Square: -b/(2a)
Step-by-step explanation:
<u>Step 1: Define</u>
x² - 8x + 15 = 0
<u>Step 2: Solve for </u><em><u>x</u></em>
- [Subtraction Property of Equality] Subtract 15 on both sides:                     x² - 8x = -15
- Complete the Square [Addition Property of Equality]:                                 x² - 8x + 16 = -15 + 16
- [Complete the Square] Simplify:                                                                   (x - 4)² = 1
- [Equality Property] Square root both sides:                                                  x - 4 = ±1
- [Addition Property of Equality] Add 4 on both sides:                                   x = 4 ± 1
- Evaluate:                                                                                                          x = 3, 5
 
        
             
        
        
        
2/9=22%
21%
21%
22%
So it would be 21%, 0.21, 11/50, 2/9.