Answer:
C
Step-by-step explanation:
I did that test before we trusty meee
Answer:
No, it's not a solution.
Step-by-step explanation:
-2 + 4(3) = 4
-2 + 12 = 10
-2 + 3(3) = 1
-2 + 9 = 7
Answer:
$44
Step-by-step explanation:
Original price = $80
Discount on sale = 50%
Discounted price = (1 - 50%) * original price
Discounted price = 0.5 * $80 = $40
Sales tax = 10%
Sales tax amount = 0.1 * $40 = $4
Total cost = discounted price + sales tax amount
Total cost = $40 + $4 = $44
Answer:
All trapezoids are quadrilaterals.
Step-by-step explanation:
Incorrect. Trapezoids have only one pair of parallel sides; parallelograms have two pairs of parallel sides. A trapezoid can never be a parallelogram. The correct answer is that all trapezoids are quadrilaterals.
Answer:
204/325
Step-by-step explanation:
You can work this a couple of ways. We expect you are probably expected to use trig identities.
cos(A) = √(1 -sin²(A)) = 24/25
sin(B) = √(1 -cos²(B)) = 12/13
cos(A -B) = cos(A)cos(B) +sin(A)sin(B) = (24/25)(5/13) +(7/25)(12/13)
= (24·5 +7·12)/325
cos(A -B) = 204/325
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The other way to work this is using inverse trig functions. It is necessary to carry the full calculator precision if you want an exact answer.
cos(A -B) = cos(arcsin(7/25) -arccos(5/13)) = cos(16.2602° -67.3801°)
= cos(-51.1199°) ≈ 0.62769230 . . . . (last 6 digits repeating)
The denominators of 25 and 13 suggest that the desired fraction will have a denominator of 25·13 = 325, so we can multiply this value by 325 to see what we get.
325·cos(A-B) = 204
so, the exact value is ...
cos(A -B) = 204/325
