Let r+ denote the set of positive real numbers. let f : r × r+ → r be given by f(x, y) = x/y.
(a) is f an injective function? prove your answer.
(b) is f a surjective function? again, prove your answer.
(c) is f a bijection? prove your answer

see below

step-by-step explanation:

x+2> 6

subtract 2 from each side

x+2-2 > 6-2

x > 4

there is an open circle at 4 since is it is greater than and the line goes to the right

the first option i believe

step-by-step explanation:

85.3-64 = 21.3

so laura has already added 85.3 grams of chocolate powder and she has gone over the amount specified in the recipe by 21.3 grams

hope i ! have a great  day!