What is the graph of each equation?
a. x = 21
b. y = 4

Lena reflected this figure across the x-axis. she writes the vertices of the image as a'(−2, 8), b'(−5, 6), c'(−8, 8), d'(−4, 2).

Pls brainliest will be awarded if answer is correct

Given the equation −4  = 12, solve for x and identify if it is an extraneous solution.