A tourist ignores the warning signs and leaves food in his car while he goes for a hike. A mama bear and her cub open the car door in 6 seconds. How long would it take each bear to open the car door alone if the cub needs 9 more seconds than the mama bear?

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

step-by-step explanation:

true

step-by-step explanation: