13) Marcus has scores of 92, 87, 85 and 88 on four algebra tests. What score must he make on his exam to receive a "B" in the course, if the final exam counts as two tests? A "B" in the course is earned if the final average is between 83 and 91. Write a compound inequality to represent this situation.

Solved

Show answers

Ответ:

spaigenicole

10.10.2021

Mathematics

9 in

Step-by-step explanation:

Use the cosine law to find the length of the longest unknown side:

$x^2=a^2+b^2-2ab\cos \alpha\\ \\x^2 =5^2+8^2-2\cdot 5\cdot 8\cdot cos \alpha\\ \\x^2 =25+64-80\cos \alpha\\ \\x^2=89-80\cos \alpha$

If the triangle is acute, then all the measure of the cosine of the greatest angle (opposite to the greatest side) is greater than 0, so

$\cos \alpha=\dfrac{x^2-89}{-80}\\ \\\dfrac{x^2-89}{-80}0\Rightarrow x^2-89<0\\ \\x\in (-\sqrt{89},\sqrt{89})$

The greatest possible whole number is 9 in

0,0(0 оценок)

Ask your question to the AI advisor

Ai-bot is an expert in any field and is the perfect companion for reliable and useful answers and advice on a variety of topics, including science, history, technology, art, sports, health, culture and more.

Ask your question

More tips

Answers on questions: Mathematics

Ask an AI advisor a question

I want advice