Answer:
in short, Yes they are always rational.
here's why...
E.g. suppose 
and 
are fractions, that means that a,b,c,d are all integers, and b and d are not zero. finding the sum the numerator, and denominator would also have to be integers. the denominator of the sum can't be zero since the denominators of the fractions were not zero, and would give 
and since they are bound by addition (sum means addition) they must also be rational since eit would equal a bigger integer than initially had
Step-by-step explanation:
Answer:
The directrix is y=6 and focus is (0,4)
The equation of the parabola is,
20-4y=x²
Sales tax is:
$62.80* (6/100)= $3.77
$62.80+ $3.77= $66.57
The cost of the skateboard including sales tax is $66.57~
The sum of the angles x and y are 127 degrees.
X + Y = 127
The measure of x is 34 more than half the y.
X = (y/2) + 34
X = (y + 68) / 2
X = 127 - Y
(Y + 68)/2 = 127-Y
254-2Y = Y+68
186 = 3Y
Y = 62
X = 127-62 = 65
The measure of two angles are 62 and 65
