An astronomer knows the distances from herself to stars AAA and BBB, as well as the distance between them. The distances are 450, 400, and 90 light years (\text{l. y.}l. y.start text, l, point, y, point, end text) respectively. If the astronomer's telescope is currently pointed at star AAA, how many degrees must she rotate her telescope to see star BBB?

10.27 degrees.

Step-by-step explanation: I did the math. :D

see explanation

step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

remove brackets and collect like terms

13 - r - 1 + r

= 12 - r

c

remove brackets and collect like terms

= - 8 - r + 2r - 4

= - 12 + r

d

remove brackets and collect like terms

= 7r - - - 6r

[-   - = - - = - ]

= r -