9514 1404 393
Answer:
-2
Step-by-step explanation:
The solution to the system is where the lines cross. The x-coordinate of that point is its horizontal distance from the y-axis.
The solution is (x, y) = (-2, 2). The x-coordinate is -2.
Answer:
X = -2 and 4
Step-by-step explanation:
Move all of the terms to one side and set the equation to 0:
2x^2-14x+40-3x^2+16x-32 = 0
Then combine all like terms which would look like the following:
-x^2 + 2x + 8=0
Change the signs on both sides of the equation:
x^2 - 2x - 8 =0
Write -2x as a difference:
x^2 + 2x - 4x -8 = 0
Factor the expression:
x(x+2) x 4(x+2)=0
Factor out x+2 from the equation:
(x+2) (x-4)=0
Split into classes and then find the answer from there:
x+2=0
x-4=0
Let us find the length of rope Jules will need using the pythagoras theorem .
Width of the moat ( let the moat be the base of this triangle ) = 14 foot
Distance from Roma's window to the boat ( let this be the side of the triangle where the right angle is present ) =20 feet
Then the length of rope needed ( hypotenuse ) =
= Let us name the triangle that is formed as △ ABC . Then ;
In △ ABC :
AB = the width of moat ( leg of triangle ) = 14 foot
BC = The distance from the window to the moat ( base ) = 20 feet
AC = Length of rope needed ( hypotenuse ) =
= AB ² + BC² = AC² ( according to the pythagoras theorem the square on the hypotenuse will be equal to the sum of the squares on the other two legs )
= 14² + 20² = AC²
= 196 + 400 = AC²
= 596 = AC²
= 24 × 24 = AC × AC
= 24 foot = AC = length of rope needed by jules .
Therefore , Jules will need a 24 foot rope so that his girlfriend can slide down and escape from her apartment .
Answer:
The 90% confidence interval using Student's t-distribution is (9.22, 11.61).
Step-by-step explanation:
Since we know the sample is not big enough to use a z-distribution, we use student's t-distribution instead.
The formula to calculate the confidence interval is given by:
Where:
is the sample's mean,
is t-score with n-1 degrees of freedom,
is the standard error,
is the sample's size.
This part of the equation is called margin of error:
We know that:
degrees of freedom
Replacing in the formula with the corresponding values we obtain the confidence interval:
