The equation become by the given age constraint is b² - 4b - 621 = 0 and Sam's age is 23 years old.
<h3>How to form an equation?</h3>
Determine the known quantities and designate the unknown quantity as a variable while trying to set up or construct a linear equation to fit a real-world application.
In other words, an equation is a set of variables that are constrained through a situation or case.
a)
As per the given,
b = Beth's age
Sam's age is s let's say.
s = b - 4
And sb = 621
s = 621/b
By substitution,
621/b = b - 4
621 = b² - 4b
b² - 4b - 621 = 0
b)
b² - 4b - 621 = 0
b² - 27b + 23b - 621 = 0
b(b - 27) + 23(b - 27) = 0
(b - 27)(b + 23) = 0
b = 27 and -23
Since, age never is negative thus b = 27 years old.
sb = 621
s = 621/27 = 23 year old.
Hence "The equation become by the given age constraint is b² - 4b - 621 = 0 and Sam's age is 23 years old".
For more about the equation,
brainly.com/question/10413253
#SPJ1