What is the first step in writing f(x) = 6x2 + 5 – 42x in vertex form?

Step-by-step explanation:

Digits after the decimal in a number decide the number of decimal places.

If there are 1 digit after the decimal, decimal place will be one decimal place.

Similarly, 2 digits after the decimal, decimal place will be two decimal place.  

1). 4.2(0.938) = 3.9396 (Four decimal places)

2). 0.9(29.3) = 26.37 (Two decimal places)

3). 18(5.75) = 103.50 (Two decimal places)

4). 0.48(12.19) = 5.8512 (Four decimal places)

5). 3.21(2.4) = 7.704 (Three decimal places)

6). 50.7(14.06) = 72.842 (Three decimal places)