Answer:
2 months
Step-by-step explanation:
you can set up equations for each sister:
(Sarah) y = 3x + 30
(Anna) y = -2x + 40
you can graph them to find where they intersect (2,36) or:
you can set them equal to each other like the following:
3x + 30 = -2x + 40
5x = 10
x = 2
90,000
this is wrong
$21
40% of 15 is 6, and 15 + 6 is 21
28, 32, 36
If you multiply each 7, 8, and 9 by 4 you get 28, 32, and 36. The sum of those numbers is 96.
