Quadratic equations - parabolas question ^^

Convert to vertex form [ which is a (x - b)^2 + c ] :-

x^2 + (x + 1)^2

= x^2 + x^2 + 2x + 1

= 2x^2 + 2x + 1

= 2( x*2 + x) + 1

= 2[ (x + 0.5)^2 - 0.25 ] + 1

= 2(x + 0.5)^2 -0.5 + 1

= 2(x + 0.5)^2 + 0.5

The last constant is the minimum value of f(x)

Answer 0.5

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.