She worked 50.5 hours last week.
7.80x40=312
352.95-312=40.95
40.95/4.90=10.5
10.5+40=50.5
Answer:
3.83
Step-by-step explanation:
Mean of x = Σx / n
Mean of x = (14 + 19 + 13 + 6 + 9) / 5 = 12.2
Sum of square (SS) :
(14-12.2)^2 + (19-12.2)^2 + (13-12.2)^2 + (6-12.2)^2 + (9-12.2)^2 = 98.8
Mean of y = Σy / n
Mean of y = (101 + 89 + 48 + 21 + 47) / 5 = 61.2
Σ(y - ybar)² = (101-61.2)^2 + (89-61.2)^2 + (48-61.2)^2 + (21-61.2)^2 + (47-61.2)^2 = 4348.8
df = n - 2 = 5 - 2 = 3
Σ(y - ybar)² / df = 4348.8 / 3 = 1449.6
√(Σ(y - ybar)² / df) = √1449.6 = 38.074
Standard Error = √(Σ(y - ybar)² / df) / √SS
Standard Error = 38.074 / √98.8
Standard Error = 3.83
The first step for solving this problem is to multiply both sides of the bottom equation by -3.

Add the two equations together.
6x - 9y - 6x + 9y = 16 - 21
Eliminate the opposites.
-9y + 9y = 16 - 21
Remember that the sum of two opposites equals 0,, so the equation becomes the following:
0 = 16 - 21
Calculate the difference on the right side of the equation.
0 = -5
This means that the statement

is false for any value of x and y. That means that the answer to your question is (x,y) ∈ ∅,, or no solution.
Let me know if you have any further questions.
:)
A quadratic equation is in the form of ax²+bx+c. The time at which the height of the ball is 16 feets is 0.717 seconds and 1.221 seconds.
<h3>What is a quadratic equation?</h3>
A quadratic equation is an equation whose leading coefficient is of second degree also the equation has only one unknown while it has 3 unknown numbers. It is written in the form of ax²+bx+c.
The complete question is:
A ball is thrown from an initial height of 2 feet with an initial upward velocity of 31 ft/s. The ball's height h (in feet) after 7 seconds is given by the following, h=2+31t-16t². Find all values of t for which the ball's height is 16 feet. Round your answer(s) to the nearest hundredth.
The time at which the height of the ball is 16 feet can be found by,
h = 2 + 31t - 16t²
16 = 2 + 31t - 16t²
16 - 2 - 31t + 16t² = 0
16t² - 31t + 14 = 0

t = 0.717 , 1.221
Hence, the time at which the height of the ball is 16 feets is 0.717 seconds and 1.221 seconds.
Learn more about Quadratic Equations:
brainly.com/question/2263981
#SPJ1
Answer:
g(6)=-16
Step-by-step explanation:
g(6)=-2(6)-4
g(6)=-12-4
g(6)=-16
Hope this helps lol