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:
208*13= 2704
Step-by-step explanation
+2
208
<u> x 13</u>
624
<u>+ 2080</u>
2704
$35.93
15% of 39.50= 33.58
7% of 33.58= 35.93