Aset of twins, andrea and courtney, are initially 10 years old. while courtney remains on earth, andrea rides on a spaceship which travels away from earth at a speed of 0.50 c for five years (as measured by courtney), then immediately turns around and comes back at 0.50c . when andrea returns, courtney is 20 years old. how old is andrea upon her return?

she is 20 at least I think not entirely sure about that!

Step-by-step explanation:

if Courtney is here on earth while her twin Andrea is in space she ages by the same rate just it's a little bit different. no one knows how long Andrea has slept for or how long she was up there for.

use this formula:

p(a\b) = p(a and b)/p(b).

take it from here.

-7

step-by-step explanation:

x^2 + 18x + 74 = (x + 9)^2 - 81 + 74

= (x + 9)^2 - 7.

so q = -7.