The expression that is listed below is equivalent to 66 • 6 - 9
Answer: 396-9
Okay, you will need to use the law of cosines for this problem.
The Law of Cosines states (in this case): a^2 = b^2 + c^2 - 2 * b * c * cos A, where "a" is the side opposite angle A (7 inches), and b and c are the other two sides.
Plug the numbers in and you get: 7^2 = 5^2 + 9^2 - 2 * 5 * 9 * cos A, or:
49 = 25 + 81 - 90 * cos A.
Subtract (25 + 81) from both sides to get:
-57 = -90 * cos A.
Divide by -90 on both sides:
cos A = 19/30
To find A, you do the inverse trigonometric function to get:
cos^-1 of (19/30) = A.
I don't have a calculator that can do this right now, but if you plug the left side of the above equation into it (make sure it is in degrees, not radians), you should get A.
<h3>
Answer: 30 feet</h3>
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Explanation:
He has 90 feet of fencing overall. This is the perimeter of the rectangle as its the distance around all four sides.
Two of the opposite sides are the width = 15 ft. So we have 15+15 = 30 feet taken up and 90-30 = 60 feet left for the other two opposite sides to add to. Call each of those sides x
x+x = 60
2x = 60
x = 60/2
x = 30
The other side must be 30 feet long.
This rectangle is 30 by 15
perimeter = 30+15+30+15 = 45 + 45 = 90
which helps confirm we have the right answer
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Or you can solve this way
P = 2*(L+W) is the perimeter of a rectangle with length L and width W
Plug in the perimeter P = 90 and the width W = 15. Solve for L
P = 2*(L+W)
90 = 2*(L+15)
2(L+15) = 90
L+15 = 90/2
L+15 = 45
L = 45-15
L = 30
Answer:
1
Step-by-step explanation:
Slope = Change in y/ Change in x
= (9-7)/(9-7)
= 2/2
