We are given
The average income, I, in dollars is

(a)
now, we are given
average income is $275000
so, 
now, we can set them equal
and then we can solve for x


we will have to use quadratic formula


we get


we need to find youngest age
It means that we need to choose smallest value
so,
............Answer
(b)
we are given
x=40
so, we can plug it and find I

..............Answer
Hello :
an equation is : y-5 = 0( x+7)...(the slope =0 '<span> horizontal line ' )</span> y=5
x² - 4x - 12 = 0
Factor the left side: (x + 2) · (x - 6) = 0
The equation is true if either factor is zero.
If (x + 2) = 0 then x = -2 .
If (x - 6) = 0 then x = 6 .
Answer:
The answer is b, which is 3+x+3