Answer:
9² = 40² + 41² - 2(40)(41) cos(C)
81 = 1600 + 1681 - 3280 cos(C)
81 = 3281 - 3280 cos(C)
-3200 = -3280 cos(C)
cos(C) = 3200 / 3280
cos(C) = 40 / 41
Step-by-step explanation:
The problem in the picture would be
x^2+10x+21
Answer:
144 and 18
Step-by-step explanation:
18 ×24=432÷3=144