Question

Use the quadratic formula to solve for x. 4x2 +9x-1=0​

Answer 1

Answer:

$x=\frac{-9\pm\sqrt{65} }{8}$

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right

Algebra I

• Standard Form: ax² + bx + c = 0
• Quadratic Formula: $x=\frac{-b\pm\sqrt{b^2-4ac} }{2a}$

Step-by-step explanation:

Step 1: Define

4x² + 9x - 1 = 0

Step 2: Define variables

a = 4

b = 9

c = -1

Step 3: Find roots

1. Substitute:                    $x=\frac{-9\pm\sqrt{9^2-4(4)(-1)} }{2(4)}$
2. Exponents:                   $x=\frac{-9\pm\sqrt{81-4(4)(-1)} }{2(4)}$
3. Multiply:                        $x=\frac{-9\pm\sqrt{81-16} }{8}$
4. Subtract:                       $x=\frac{-9\pm\sqrt{65} }{8}$