Answer:
k = - 2
Step-by-step explanation:
( 2x - y )²
Formula : -
( a - b )² = a² + b² - 2ab
Here,
a = 2x
b = y
( 2x - y )²
= ( 2x )² + y² - 2 ( 2x ) ( y )
= 4x² + y² - 4xy
So,
( 2x - y )² = 4x² + y² - 4xy
( 2x + y )²
Formula : -
( a + b )² = a² + b² + 2ab
Here,
a = 2x
b = y
( 2x + y )²
= ( 2x )² + y² + 2 ( 2x ) ( y )
= 4x² + y² + 4xy
So,
( 2x + y )² = 4x² + y² + 4xy
( 2x - y )² - ( 2x + y )²
= 4x² + y² - 4xy - ( 4x² + y² + 4xy )
= 4x² + y² - 4xy - 4x² - y² - 4xy
= 4x² - 4x² + y² - y² - 4xy - 4xy
= 0 + 0 - 8xy
= - 8xy
( 2x - y )² - ( 2x + y )² = 4xyk
- 8xy = 4xyk
Divide 4xy on both sides,
- 8xy / 4xy = 4xyk / 4xy
- 2 = k
k = - 2
Therefore, the value of k is - 2.
9514 1404 393
Answer:
17) x = 10√2
18) x = 4√6
Step-by-step explanation:
These problems rely on your knowledge of the side ratios of special triangles
45°-45°-90° triangle: 1 : 1 : √2
30°-60°-90° triangle: 1 : √3 : 2
__
17) 5 is the short side of the isosceles right triangle, so its hypotenuse is 5√2. That length is the shortest side of the 30/60/90 triangle, so its longest side is 2 times that:
x = 10√2
__
18) 8 is the longest side of the 30/60/90 triangle, so its long leg will be 8(√3)/2 = 4√3. The hypotenuse of the isosceles right triangle is √2 times that, so ...
x = (4√3)(√2)
x = 4√6
Answer 3 3/14
(7/8) times (45/14)= 45/16. Got 45/16 from 2 13/16
Answer:
7:59
Step-by-step explanation:
Answer:
<h2>D. Quadrant III</h2>
Step-by-step explanation:
Quadrant in coordinate geometry is divided into four parts which is called Quadrants.
Quadrants I (x, y)
Quadrants II (-x, y)
Quadrants III (-x, -y)
Quadrants IV (x, -y)
so W(-3, -9) both are negatives so its lie on Quadrants III
