Question

Factor the following quadratic function:

-
y = 7x2
- 48x - 7

How do I do it

Answer 1

(7x + 1)(x - 7).

Explanation:

y = 7x^2 - 48x - 7

Use the 'ac' method:

7 * 7 = 49

Now we need 2 numbers whose product is 49 and whose sum is the 'middle' number -48.

They are -49 and 1,

Now we write the function as:

7x^2 - 49x + 1x - 7

= 7x((x - 7) + 1(x - 7) (x - 7) is common so we have

(7x + 1)(x - 7).