The family tree below shows the trait of having attached earlobes. Having attached earlobes is recessive, and having detached earlobes is dominant. People with attached earlobes are shaded in. a) Describe the sex and characteristics of the person labeled A.

b) Describe the genotype of the person labeled B.

c) Describe the genotype of the person labeled C.

d) Could the person labeled D have a recessive allele?

answer-

the statement that f(x) = |x+a| + b has exactly one x-intercept is sometimes correct.

solution-

it solely depends on b, whether the function will have one or two or zero x intercept.

this plot of the given function, f(x) = |x+a| + b will be the basic absolute value graph i.e v shape, with vertex translated to (-a, b), instead of origin.

1-   if b is zero, the graph will have exactly one x-intercept, at x= -a

2- if b is positive, the whole graph will be above the x-axis, hence it will have no x-intercepts.

3- if b is negative, the graph will be below the x-axis, hence it will have two x-intercepts.

∴ the statement is sometimes true.