## Example Questions

### Example Question #1 : How To Use The Quadratic Function

Two consecutive negative odd numbers have a product of 15. What is the sum of the two numbers?

–6

–8

–10

–4

–12

–8

Explanation:

Define the variables x = first number and x + 2 = second number

The product is x(x + 2) = 15, so we need to solve the quadratic equation x2 + 2x – 15 = 0.  Factoring we get (x + 5)(x – 3) = 0, so x = –5 or x = 3.  The problem calls for negative numbers, so the answers are –5 and –3 and the sum is –8

### Example Question #1212 : Algebra

What is the difference of the values of x that satisfy

4x2+ 3x – 1 = 0?

3

0

4/5

5/4

5/4

Explanation:

Factor the equation (4x – 1) (x + 1)

The solutions are x = –1 and x = 1/4.

The difference is (1/4) – (–1) = 5/4

### Example Question #2 : How To Use The Quadratic Function

2x + y = 1

What is the slope and the y-intercept of the given equation, respectively?

1, 2

1, 1

–2, 1

2, –2

2, 1

–2, 1

Explanation:

You put the equation into slope-intercept form (y = mx b)

The new equation is y= –2x + 1

= –2 and = 1

### Example Question #1213 : Algebra

How many solutions are there to: x– 9 = 0

Infinitely many

1

2

0 