The answer is obtuse
a = 4
b = 28
c = 31
If a² + b² > c² - the angle is acute
If a² + b² < c² - the angle is obtuse
If a² + b² = c² - the angle is right
a² + b² = 4² + 28² = 16 + 784 = 800
c² = 31² = 961
800 < 900
a² + b² < c²
Therefore, the angle is obtuse
To solve this inequality, you need to isolate the value of u. To do this, divide both sides by -2. When you do this, keep in mind that when you divide or multiply both sides by a negative in an inequality, you MUST flip the sign, so your answer would be -8 < u or u > -8.
Answer:
80 parrots were purchased.
Step-by-step explanation:
Let the total number of parrots be k.
If 20% (or 20/100 = 1/5) flew away and 5% (5/100 = 1/20) died, the remaining parrots will be k – (¹/₅k + ¹/₂₀k) = k – ¼k = ¾k.
Of the remaining, 45% (or 45/100 = 9/20) were sold, which means the total number of sold parrots will be ¾k × ⁹/₂₀ = ²⁷/₈₀k.
The remaining parrots = ¾k – ²⁷/₈₀k = ³³/₈₀k = 33
k = 33 × ⁸⁰/₃₃ = 80 parrots were purchased.