Question

A student is deriving the quadratic formula. Her first two steps are shown. Step 1: –c = ax2 + bx Step 2: -c = a[x^2+b/ax] Which best explains or justifies Step 2? division property of equality factoring the binomial completing the square subtraction property of equality

Answer 1

answer is B

Explanation:

Answer 2

Given choices:

(1) division property of equality

(2) factoring the binomial

(3)completing the square

(4)subtraction property of equality

Answer : (2) factoring the binomial

Step 1:
`-c = ax^2 + bx`

Step 2:
`-c = a[x^2+(b)/(a) x]`

In step 2, 'a' is taken out from
`ax^2 + bx`. when we take out 'a' we divide each term by 'a'. so it becomes
`a[x^2+(b)/(a) x]`

'a' is factored out in step 2. we call it as factoring a binomial.