Answer:
Tổng 3 góc trong 1 tam giác là 180 độ
Vậy góc B = 180 - A - C = 180 - 90 - 50 = 40 độ
I think you mean x^2 - 7x + 8
This is a basic factoring problem:
What two numbers multiply to make 8 and add to make -7?
There are no two numbers that work!
Therefore, it is prime
Answer:
To be precise, I think it's a pattern question, where you have to add 4 to each number. I'm not very sure though.