9(n+7) = 18(n+1)
9n + 63 = 18n + 18
9n = 45
n = 5
answer
n = 5
Answer:
45 horseshoe crabs and 45 sea stars
Step-by-step explanation:
The aquarium initially contained x crabs and x sea stars.
"After 15 horseshoe crabs and 27 sea stars are removed the ratio of horseshoe crabs to sea stars is 5:3"
(x-15):(x-27) = 5:3
(x-15)/(x-27) = 5/3
3(x-15) = 5(x-27)
3x-45 = 5x-135
90 = 2x
x = 45
Answer: A. The original price was $608. B. $76 each week C. Quite useful, as it keeps track of the amount of money she still needs to owe each week.
Step-by-step explanation: For part A, 5 week subtracted by 2 weeks is 3 weeks. 456-228 is 228. Then divide 228 by 3 and you get $76. Then do 2x76 to get 152 and add it to 456, and you get 608.
Answer:
(a, b, c) = (30°, 60°, 105°)
Step-by-step explanation:
Angle "a" and 30° are vertical angles, hence equal.
Angle "b" and angle "a" are complementary angles, so b = 90° -30° = 60°.
Angle "c" is supplementary to the one marked 75°, so is 180° -75° = 105°.
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Angles "a" and "b" are complementary because the sum of angles in a triangle is 180° and the third angle in that triangle is 90°. Then ...
a+b = 180°-90° = 90°
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75° and "c" are supplementary, because they are linear angles. The angle measure of a line is 180°, so that is their total measure.
