Which graph represents a function? i think a.

graph B ( the lower one )

for a function to be defined there can only be one value of y for each value of x

graph A has more than 1 value of y for given values of x

for example ( - 1, 4 ) and  ( - 1, - 4 ) thus is not a function

graph B only has 1 value of y for a given value of x thus is a function

x is greater than 5

step-by-step explanation:

2x+7 is greater than 17

    -7                           -7

2x is greater than 10

divide by 2 each side

x is greater than 5