Some of the steps in the derivation of the quadratic formula are shown. Step 3: –c + b^2/4a=a(x^2+b/ax+b^2/4a^2 step4a: -c+b^2/4a=a(x+b/2a)^2 step4b: -4ac/4a+b^2/4a=a(x+b/2a)^2 Which best explains or justifies Step 4b? factoring a polynomial multiplication property of equality converting to a common denominator addition property of equality

(C)Converting to a common denominator

Step-by-step explanation:

Given some of the steps in the derivation of the quadratic formula below:

Step 4b is derived from Step 4a by converting the left-hand side to a common denominator 4a.

Therefore, that which best explains or justifies Step 4b is:

(C)Converting to a common denominator

blue marble is 15 times out of 50 = 15/50 reduces to 3/10

landing on tails is 24 out of 50 = 24/50 reduces to 12/25

to find the probability of both multiply together:

3/10 x 12/25 = 3 x 12 / 10 x 25 = 36/250

if you multiplied the numerator and denominator by 10 you get 360/2500.

the answer is 360/2500