The best answer to go with is b you’re welcome have a great day
Answer:
45
Step-by-step explanation:
Correct! lines that have undefined slopes are always parallel to the y-axis as the change in x is 0. A gradient is calculated by the change in y divided by the change in x and anything divided by 0 is referred to as undefined.
(calculation for a gradient)
Hope that helps sorry if its a bit confusing :)
Two planes intersect in a line..I think because planes are not lines