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.
Answer:
Y= 3/5-4
Step-by-step explanation:
What is slope-intercept form? Slope intercept form is an equation for graphing. It is y=mx+b. The "m" stands for the slope, or how much coordinates it takes to move to the next point. The "b" stands for the y-intercept, or where the line is perfectly on the y-line.
Step One: The first part of the equation is the slope, so let's figure that out. Since this one a graph, it is easy to tell the slope. The points are nicely marked, so we don't have to guess which points are visible. We are going up 3 jumps and then across 5 jumps. The slope is always "rise/run" where the "rise" is the y and "run" is x. So, the slope is 3/5x.
Step Two: For the last part, we need to know the y-intercept. It is clearly shown on the graph: -4. Because it is negative, we remove the plus sign because a plus with a negative is subtraction.
Step Three: We can combine both parts and that is the answer: y=3/5x-4.
Divide 20 by 3 to see how much she would wax in 1/5 of an hour.
20/3= 6.66666667
6.66666667 * 5 =
33.3333333
i think :)
A) The estimated total expense is
.. $600 +300 +200 +100 +200 = $1400
b) The estimated remaining to be saved is
.. $1400 -800 = $600
Answer:
maybe A
Step-by-step explanation: