Hello!
Judging by the question you have provided I have figured that the best way to go about finding the solution is by using the distributive property!
This means you will want to distribute the y = -3 into the 2y+7-4y-10 equation.
However, the first step you should take is to simplify the equations.
After simplifying the equations you should come out with the new equation being -2y-3.
You now want to distribute the y=-3 into the equation!
You should get -2(-3)-3. Now solve!
The answer you get should be 3!
Hope this helped!
-Blake
7 Expand and simplify where necessary
a 3(4p + 1)
b -6(3T + 5)
ç 4(3x – 2y) + 4(x + 4y)
d 7(2m - 3) - 9(y - 1)
Summary
pretty simple dont suck
Answer:
2) B. as x increases, y increases as well
3) C. Number of books owned and number of visits to the doctor's office in one year
4) D. The 90 minute lesson that cost $40
5) A. There is a strong correlation
Step-by-step explanation:
2) i am not 100%positive since there is no way to check my answer, but i believe it is "B. As x increases, y increases as well" because it highlights the correlation between x and y.
(i already explained 3, 4, and 5 on another one :D)
Answer:
Only C is a function
Step-by-step explanation:
To test whether a graph is a function you use the vertical line test.
If you can place a vertical line anywhere on the plane (in the domain of the "function" to be tested) and it intersects the curve at more than one point, the curve is not a function.
We see with A, wherever we put the vertical line it intersects twice.
With B, it intersects infinitely many times.
C is a function because wherever we put the vertical line, it only intersects once.
D is a function because it intersects twice providing we do not put it on the "tip" of the parabola.
The mathematical reasoning behind this is that a function must be well-defined, that is it must send every x-value to one specific y-value. There can be no confusion about where the function's input is going. If you look at graph B and I ask you what is f(3)? Is it 1? 2? 3? ... Who knows, it's not well-defined and so it's not a function. However if I ask you about C, whichever input value for x I give you, you can tell me to which y-value it gets mapped/sent to.
4) You know slope-intercept form is y=mx+b. So using these two given points, you can find the slope!
(-8,5) (-3,10) [Use the y1-y2 over x1-x2 formula to solve for slope]
10 - 5 5
--------- = ----- = 1
-3-(-8) 5
Hurray! You got a slope of one. Now substitute this back into your original equation:
y=mx+b --> y=1x+b
Next, we find what our "b" is, or what our y-intercept is:
Using one of the previous points given, substitute them into the new equation:
[I used the point (-3, 10) ]
y=1x+b
10=1(-3)+b SUBSTITUTE
10=-3+b MULTIPLY
10=-3+b
+3 +3 ADD
----------
13=b SIMPLIFY
So, now we have our y-intercept. Use this and plug it into the equation:
y=1x+b --> y=1x+13
y=1x+13 is our final answer.
5) So for perpendicular lines, your slope will be the opposite reciprocal of the original slope. (Ex: Slope is 2, but perpendicular slope is -1/2)
We have the equation y= 3x-1, so find the reciprocal slope!
--> y=-1/3x-1
Good! Now we take our given point, (9, -4) and plug it into the new equation:
y=-1/3x-1
-4=-1/3(9)+b SUBSTITUTE and revert "-1" to "b", for we are trying to find the y- -4=-3+b intercept of our perpendicular equation.
+3 +3 ADD
--------
-1=b SIMPLIFY
So, our final answer is y=-1/3x+(-1)
6) I don't know, sorry! :(
