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9² = 12² + 15² - 2 (12) (15) cos (B)
81 = 144 + 225 - 360 cos(B)
81 = 369 - 360 cos (B)
360 cos (B) = 369 - 81
360 cos (B) = 288
cos (B) = 0.8
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Answer: Cosine B = 0.8
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12² = 15² + 9² - 2 (15)(9) cos (A)
144 = 225 + 81 - 270 Cos A
144 = 306 - 270 Cos A
270 Cos A = 162
Cos A = 3/5 or 0.6
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Answer: Cosine Angle A = 3/5
If there are 8 groups of 65 students, that means they can seat 8*65 students total. 520 students
Question 1:
To start off this question, we can tell that this is a square because it has 4 right angles and 4 congruent sides.
A square has four parallel sides and 4 congruent sides, so a square is a rhombus and parallelogram.
A square has 4 right angles, so it's also a rectangle.
A square has 4 sides, so it's also a quadrilateral.
The first choice is your answer.
Question 2:
Not all quadrilaterals are rectangles, so A is incorrect.
Not all quadrilaterals are squares, so B is incorrect.
All rectangles are types of quadrilaterals, so C is correct.
Not all quadrilaterals are parallelograms, so D is incorrect.
Thus, C is your answer.
Question 3:
The first choice will not work because a rhombus will satisfy those conditions, and a rhombus is not always a square.
The second choice will work because only a square will satisfy that condition because only squares have 4 congruent sides along with equal diagonals.
Thus, the second choice is your answer.
Have an awesome day! :)
2x^2-7x-4=0
2x^2-8x+x-4=0
2x(x-4)+1(x-4)=0
(2x+1)(x-4)=0
x=-1/2, 4
Answer:
y=3x-8
Step-by-step explanation:
If the line is parallel to y=3x+3, that would mean that they would have the same slope of 3. Then, once you plug it back into the equation along with the point given, you would get 1=3(3)+b. Solve from there, and you get b= -8. In conclusion, your point slope formula comes out to be y=3x-8.
Hope this helps! :)