2×+y=0,
×-y=6
Add the 1st to the 2nd equation==> 3x +y-y=6+0==> 3x=6 & x=2
Plug 2 into any of the equation & you will get y=-4
Answer:
E IS THE CORRECT ANSWER
The R-squared is 0.64 and it means that the dependent value explains 64% of the independent value in the simple regression analysis
Step-by-step explanation:
R-Squared value is a very important indicator in a regression analysis.
What does it measure?
It measures how close to the line of best fit are the data points. How good the fitted line is can be indicated by the value of the r-squared.
The maximum value it can take is 1 and at this value, there is a direct and complete relationship between the independent variable x and the dependent variable y. The value 1 represents an 100% relationship between both parties.
The r-squared has a value of between 0 and 100%. The closer to 100, the better the model while the closer to 100, the more faulty the model is. In fact, a value of 0 indicates no relationship at all between the dependent and the independent variable.
With an R-squared value of 0.64, the regression model works above average to explain that the dependent variable explains 64% of the independent value in the simple regression analysis.
This does not appear to be a right triangle. However, we know 2 sides and the included angle, so can find the unknown side length. Let x represent this length. Then:
x^2 = (9 m)^2 + (12 m)^2 - 2(9m)(12 m)*cos 30 degrees, or
x^2 = 81 + 144 - 216(sqrt(3) / 2). Please solve for x^2 and then solve the result for x, making sure to choose the positive value. The result will be the length of the side opposite the 30 degree angle.
With 1 of 3 angles known, and 3 of 3 sides known, you can use the Law of Sines to find the other two angles. As a reminder, the Law of Sines looks like this:
a b c
-------- = --------- = ----------
sin A sin B sin C.
You can give the 30-deg angle any name you want; then a, the length of the side opposite the 30-deg angle, which you have just found. And so on.
Answer:
2x + 4
Step-by-step explanation:
Let R = Ralph's age
and x = Sarah's age
Then Ralph's age in 4 years = R + 4
and Sarah's age in four years = x + 4
Thus, R + 4 = 2(x + 4)
Distribute the 2 R + 4 = 2x + 8
Subtract 4 from each side R = 2x + 4
Ralph's age is 2x + 4.
