Testing

Students of high school have 10 points for each good solved task. The wrong answer is deducted by 5 points. After solving 20 tasks, student Michael had 80 points. How many tasks did he solve correctly and how many wrong?

Correct answer:

a =  12
b =  8

Step-by-step explanation:


a+b = 20
10a - 5b = 80

a+b = 20
10•a - 5•b = 80

a+b = 20
10a-5b = 80

a = 12
b = 8

Our linear equations calculator calculates it.



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