
Dayv O. answered 12/12/23
Caring Super Enthusiastic Knowledgeable Pre-Calculus Tutor
by observation the point (1,1,1) satisfies first three equations.
now want a+b+c=0 using (1,1,1)
which is satisfied when a+b=-c
choosing any value of c have linear equation for values
of a and b. Infinitely many a and b for infinitely many choices of c.