I won't answer them all for you (don't want to cheat - need to learn something).
But for the first one given:
<span>-2x-9y=-25
-4x-9y=-23
you set up either x or y (which ever one you want to eliminate) so that one of them cancels.
So this one is easy - you just have to multiply an entire row by negative (doesn't matter which one) - so that the y's will be + and -
Since they're both 9 and they're subracting NOW - you can eliminate the y value. Now add/subtract the x's. So it'd be -2 or 2 depending on how you eliminated y. Then add the number outside of the = sign. Now just solve for x. After that plug in whatever you got for x into both of the rows. Then find the y value.
Hopefully this wasn't confusing -- reply if it is and I will try to simplify. I can give you contact if you need help with the rest
Good luck!</span>
Answer:
Step-by-step explanation:
You need to assume that the slope between the dependent Varian and the numerical independent variable is zero.
In regression analysis, to find the effect of one independent variable on the dependent variable, there has to be no interference from the other independent variables whether they be categorical (dummy) or numerical independent variables.
A dummy variable is one which takes on the value of 0 or 1, to represent the absence or presence (respectively) of a given category which is expected to influence the dependent variable.
When a dummy independent variable is included in a regression model, to know the effect of that dummy or category (e.g. day =1, night =0) on the dependent variable, the influence of the numerical independent variable has to be removed temporarily.
In a regression equation,
Y=a+bX+cK
Y is the dependent variable
a is the intercept on the vertical axis on the graph
b is the slope between the dependent variable Y and the independent numerical variable X
c is the slope between the dependent variable Y and the dummy variable K
Answer:
y-intercept = 4
x-intercept = 2
Step-by-step explanation:
you can divide the equation through by 4 and change into the y=mx+c form to find c, the y intercept so the y-intercept = 4.
for the x intercept make the y=0 (because the coordinate point where the line crosses the x axis must have y=0) and then you get 8x=16 so x=2
Answer: number 7. 7
Step-by-step explanation:
Simplifying
7X + 1 + -5X = 15
Reorder the terms:
1 + 7X + -5X = 15
Combine like terms: 7X + -5X = 2X
1 + 2X = 15
Solving
1 + 2X = 15
Solving for variable 'X'.
Move all terms containing X to the left, all other terms to the right.
Add '-1' to each side of the equation.
1 + -1 + 2X = 15 + -1
Combine like terms: 1 + -1 = 0
0 + 2X = 15 + -1
2X = 15 + -1
Combine like terms: 15 + -1 = 14
2X = 14
Divide each side by '2'.
X = 7
Simplifying
X = 7