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Graph f(x) = 2x + 4
Can you show me the graph?
Thank you,
Ashley 1 solutions
Answer 40886 by funmath(2925) on 2006-11-03 16:46:43 (Show Source):
You can put this solution on YOUR website!Hi Ashley,
Graph f(x) = 2x + 4
:
f(x)=y on the coordinate system:
y=2x+4
Let x=0 and solve for y
y=2(0)+4
y=0+4
y=4, plot (0,4)
Now let y=0 and solve for x
0=2x+4
0-4=2x+4-4
-4=2x
-4/2=2x/2
-2=x Plot (-2,0)
Connect the points and you have this line:

Happy Calculating, Ashley!!!
|
Coordinate-system/59498: Can someone help me solve the system by graphing it for me?
x - y = 5
x + y = 3
Thank you so much.
Lyn 1 solutions
Answer 40885 by funmath(2925) on 2006-11-03 16:41:06 (Show Source):
You can put this solution on YOUR website!Hi Lyn,
E1) x - y = 5
E2) x + y = 3
:
For E1) let x=0 and solve for y:
0-y=5
-y=5
-1(-y)=-1(5)
y=-5 Plot (0,-5)
Now let y=0 and solve for x:
x-0=5
x=5 Plot (5,0)
Connect the points and you have this line:

For E2) let x=0 and solve for y:
0+y=3
y=3 Plot (0,3)
Now let y=0 and solve for x:
x+0=3
x=3 Plot (3,0)
Connect the points and you have a second line:

They intersect at: (4,-1)
Happy Calculating, Lyn!!!
|
Linear-systems/59500: Can someone help me solve the system by graphing it for me?
I have to send it through the computer.
x - 2y = 8
x + y = -1
Thank you so much,
Lyn 1 solutions
Answer 40883 by funmath(2925) on 2006-11-03 16:30:22 (Show Source):
You can put this solution on YOUR website!Hi Lyn,
I saw some questions by you about graphing inequalities. I can only graph equalities or I would have answered those also.
Can someone help me solve the system by graphing it for me?
I have to send it through the computer.
E1) x - 2y = 8
E2) x + y = -1
:
For E1, let x=0 and solve for y
0-2y=8
-2y/-2=8/-2
y=-4 Plot (0,-4)
Now let y=0 and solve for x:
x-2(0)=8
x-0=8
x=8 Plot (8,0)
Connect the points and you have a line:

For E2, let x=0 and solve for y:
0+y=-1
y=-1 Plot (0,-1)
Now let y=0 and solve for x:
x+(0)=-1
x=-1 Plot (-1,0)
Connect the points and you have a second line:

They intersect at (2,-3)
I think I did this one earlier today. Maybe it was for someone else.
Happy Calculating, Lyn!!!
|
Linear-equations/59533: This question is from textbook Algebra 1
Ok, my teacher tries to explain how to get the answer and graph it. Will You explain the whole process of graphing linear equationsand functions
1 solutions
Answer 40881 by funmath(2925) on 2006-11-03 16:17:09 (Show Source):
You can put this solution on YOUR website!Here's one way to do it. I did this problem for someone else earlier today.
Graph f(x) = 3x + 2
f(x) is the same thing as y, so you graph this the same way as y=3x+2
Let x=0 and solve for y:
y=3(0)+2
y=0+2
y=2 Plot (0,2)
Let x=1 and solve for y
y=3(1)+2
y=3+2
y=5 Plot (1,5)
Connect the points and you have a line.

Happy Calculating!!!
|
logarithm/59599: Evaluate log5(3125). I am not sure how to make the 5 small just below the g on log. 1 solutions
Answer 40879 by funmath(2925) on 2006-11-03 16:05:02 (Show Source):
You can put this solution on YOUR website!Evaluate log5(3125). I am not sure how to make the 5 small just below the g on log.
To evaluate this you have to use the cahnge of base formula and a scientific calculator.
Change of base formula is:  or log(b)/log(a)
log5(3125)=ln(3125)/ln(5)=8.047189562/1.609437912=5
:
If you knew that 3125=5^5 then
log5(3125)=log5(5^5)=5
Happy Calculating!!!
|
logarithm/59600: Write the expression logb(x-1)+3logb(x-2)-2logb(x+3) as a single logarithm. Assume that the variables represent positive numbers. 1 solutions
Answer 40876 by funmath(2925) on 2006-11-03 15:48:19 (Show Source):
You can put this solution on YOUR website!Write the expression logb(x-1)+3logb(x-2)-2logb(x+3) as a single logarithm. Assume that the variables represent positive numbers.
Rules we'll use:
1. 
2. 
3. 
:
 rule 1
 rule 2

:
Happy Calculating!!!
|
logarithm/59601: Express the expression log2x^3z/y^2 in terms of logarithm of x, y, and z. 1 solutions
Answer 40875 by funmath(2925) on 2006-11-03 15:39:01 (Show Source):
You can put this solution on YOUR website!I'm not sure whether you meant 2 to be the base of the log or the coefficient of x. I'm going to solve this as a common log with 2 as the coeffiecient of x. If you want it to be the base just make 2 the base of all the logs and remove it as the coefficient of x.
:
Express the expression  in terms of logarithm of x, y, and z.
:
Rules I'm using:
1. 
2. 
3. 
:
 rule 1&2. This might be all you need
 rule 3
Happy Calculating!!!
|
Percentage-and-ratio-word-problems/59610: Ninety-five percent of cars are parked in one space in the parking lot. If 8 cars are taking two spaces, how many cars are parked in one space? 1 solutions
Answer 40873 by funmath(2925) on 2006-11-03 15:23:23 (Show Source):
You can put this solution on YOUR website!Ninety-five percent of cars are parked in one space in the parking lot. If 8 cars are taking two spaces, how many cars are parked in one space?
:
I am not sure if this is the easiest way to do this, but here's one way to do this.
If 95% parked in 1 space, then 100%-95%=5% parked in two spaces.
Let the total number of cars be x:
then
.05x=8
.50x/.05=8/.05
x=160
Once you find that then, 160-8=152 parked in one space.
You can also say, .95(160)=152 parked in one space.
:
Here's another way to set this up. Set up a proportion of 95% to 5% equal to x to 8:

Happy Calculating!!!
|
Geometry_Word_Problems/59609: The sum of the perimeters of two squares is 40 inches. the sum of their areas is 58 square inches. What are the dimensions of the squares? 1 solutions
Answer 40871 by funmath(2925) on 2006-11-03 15:09:32 (Show Source):
You can put this solution on YOUR website!The sum of the perimeters of two squares is 40 inches. the sum of their areas is 58 square inches. What are the dimensions of the squares?
:
Let the sides of one square be: x
Let the sides of the other square be:y
:
The perimeter of a square is:  , p=perimeter, s=side
E1) Therefore the sum of the perimeters is 40 is: 
:
The area of a square is:  , A=area, s=side
E2) Therefore the sunm of their area is 58 is: 
:
Therefore you have two equations and two unknowns. Solve E1 for either variable, I'm going with y.
4x+4y=40
-4x+4x+4y=-4x+40
4y=-4x+40

y=-x+10
Substitute that into E2 for y and solve for x:
 Factor
(x-3)(x-7)=0 set each parentheses = to 0
x-3=0 and x-7=0
x-3+3=0+3 and x-7+7=0+7
x=3 and x=7
If you were to substitute either x into E1 you'd get the other x
4(3)+4y=40
12+4y=40
4y=28
4y/4=28/4
y=7 You can check 7 for yourself, you'll get 3.
One square is 3 in x 3 in
the other is 7 in x 7 in
Happy Calculating!!!
|
Money_Word_Problems/59590: Could someone help me solve this problem?
Lane invested $14,000, part at 15% and part at 2%. If the total interest at the end of the year is $1,060, how much did she invest at 15%?
(A) $8,000 (B) $7,000 (C) $6,000 (D) $5,000
Thank you so much,
Lyn 1 solutions
Answer 40861 by funmath(2925) on 2006-11-03 13:40:31 (Show Source):
You can put this solution on YOUR website!Hi Lyn,
Lane invested $14,000, part at 15% and part at 2%. If the total interest at the end of the year is $1,060, how much did she invest at 15%?
(A) $8,000 (B) $7,000  $6,000 (D) $5,000
:
Let the amount at 15% be: x
Then the rest of the 14,000 is invested at 2%: 14,000-x
The formula for simple interest is  , I=interest, P=principle, r=rate, and t=time (in years)
:
The interest earned at 15% is: (15/100)x=.15
The interest earned at 2% is (2/100)(14,000-x)=.02(14,000-x)
The total interest whe you add them together is: 1,060
:
Problem to solve:
.15x+.02(14,000-x)=1,060
(100).15x+(100).02(14,000-x)=(100)1,060
15x+2(14,000-x)=106,000
15x+28,000-2x=106,000
13x+28,000=106,000
13x+28,000-28,000=106,000-28,000
13x=78,000
13x/13=78,000/13
x=6,000
The amount invested at 15% is: x=$6,000
:
Now for fun, find out how much was invested at 2%.
Happy Calculating!!!
|
Graphs/59592: Could someone help me graph the following problem?
Can you show me the graph because I have to send it through the computer and need help.
Graph f(x) = 3x + 2
Thank you so much,
Lyn 1 solutions
Answer 40860 by funmath(2925) on 2006-11-03 13:19:55 (Show Source):
You can put this solution on YOUR website!Hi Lyn,
Graph f(x) = 3x + 2
f(x) is the same thing as y, so you graph this the same way as y=3x+2
Let x=0 and solve for y:
y=3(0)+2
y=0+2
y=2 Plot (0,2)
Let x=1 and solve for y
y=3(1)+2
y=3+2
y=5 Plot (1,5)
Connect the points and you have a line.

Happy Calculating, Lyn!!!
|
Exponential-and-logarithmic-functions/59585: Page 42, Question #82: Evaluate each expression; 6-(-8)^2 over -3-(-1). 1 solutions
Answer 40857 by funmath(2925) on 2006-11-03 12:36:37 (Show Source):
You can put this solution on YOUR website!Page 42, Question #82: Evaluate each expression; 6-(-8)^2 over -3-(-1).
Is this what you mean?
You treat the numerator and denominator as if they were parentheses. Simplify them completely and then divide if possible.
 Exponent
 Add/subtract
 divide
Happy Calculating!!!
|
Quadratic_Equations/59583: This question is from textbook college algebra
3x^2-7x=0
3x^2+33=2x^2+14x
(x-3)^2=9
(3x-6)^2=4x^2 1 solutions
Answer 40855 by funmath(2925) on 2006-11-03 12:16:19 (Show Source):
You can put this solution on YOUR website! Factor out the GCF
x(3x-7)=0 Set each part = to 0 and solve for x
x=0 and 3x-7=0
x=0 and 3x-7+7=0+7
x=0 and 3x=7
x=0 and 3x/3=7/3
x=0 and x=7/3
:
 Set the problem = to 0
 Factor
(x-11)(x-3)=0 Set each parentheses = 0 and solve for x.
x-11=0 and x-3=0
x-11+11=0+11 and x-3+3=0+3
x=11 and x=3
:
 use the square root property, take the square root of both sides.

x-3=+\-3
x-3+3=3+\-3
x=3-3 and x=3+3
x=0 and x=6
:
 Square the left
 Set = to 0
 Factor, I'm using the ac, arch, or grouping method.
 set each parentheses = to 0 and solve for x.
x-6=0 and 5x-6=0
x-6+6=0+6 and 5x-6+6=0+6
x=6 and 5x=6
x=6 and 5x/5=6/5
x=6 and x=6/5
:
Happy Calculating!!!
|
Quadratic_Equations/59581: I can't seem to get these right - help would be appreciated:
(Not necessary to find the roots - just determine the number & type of solution) use a discriminant to determine the number of solutions for the quadratic equasions - and if the solutions are real or complex.
a. 2x^2+x-1=0
b. 4/3x^2-2x+3/4=0
c. m^2+m+1=0
Thank you very much! 1 solutions
Answer 40854 by funmath(2925) on 2006-11-03 11:38:42 (Show Source):
You can put this solution on YOUR website!(Not necessary to find the roots - just determine the number & type of solution) use a discriminant to determine the number of solutions for the quadratic equasions - and if the solutions are real or complex.
:
The discriminant of a quadratic equation written in standard form  is 
If the discriminant is positive, there are two real solutions.
If the discriminant is 0, there is one real solution.
If the discriminant is negative, there are two complex solutions.
:
a. 2x^2+x-1=0 a=2, b=1, c=-1

=  The discriminant is positive, there are two real solutions.
:
b. 4/3x^2-2x+3/4=0 a=4/3, b=-2, c=3/4

=
 The discriminant is 0, there is one real solution.
:
c. m^2+m+1=0 a=1, b=1, c=1

= 
=  The discriminant is negative, there are two complex solutions.
:
Happy Calculating!!!
|
Linear-equations/59576: This question is from textbook The Learning Equation
A line passes through (-4,2) and has the same y-intercept as 2x-y=3. Put this in standard form. 1 solutions
Answer 40833 by funmath(2925) on 2006-11-03 08:52:13 (Show Source):
You can put this solution on YOUR website!A line passes through (-4,2) and has the same y-intercept as 2x-y=3. Put this in standard form.
This is a thinker.
To find the y-intercept of the equation of a line you can let x=0 and solve for y.
2(0)-y=3
0-y=3
-y=3
-(y)=-(3)
y=-3 The y-intercept is (0,-3)
To find an equation of a line we need a slope and a point. We don't have a slope, but we do have two points. We can find the slope between two points with the slope formula: 
(x1,y1)=(-4,2) and (x2,y2)=(0,-3)

Now we can use the slope, m=-5/4 and the y-intercept (0,b)=(0,-3) To make an equation of a line with the slope intercep formula  , m=slope, and (0,b) is the y-intercept.

Happy Calculating!!!
|
Linear-systems/59520: I need some help on this problem:
I need to solve the system by substitution
x + y = 12
y = 2x
Jamie 1 solutions
Answer 40791 by funmath(2925) on 2006-11-02 21:49:48 (Show Source):
You can put this solution on YOUR website!Hi Jamie,
Solve the system by substitution
L1) x + y = 12
L2) y = 2x
Substitute 2x into L1 and solve for x:
x+(2x)=12
3x=12
3x/3=12/3
x=4
Substitute 4 into L2 and solve for y:
y=2(4)
y=8
The solution is (x,y)=(4,8)
Happy Calculating!!!
|
Geometric_formulas/59544: My son and I need help
Can you tell us how to solve this problem?
V=Pi r^2 h solve for r. 1 solutions
Answer 40790 by funmath(2925) on 2006-11-02 21:42:40 (Show Source):
You can put this solution on YOUR website!The goal is to get the r all by itself. To get rid of the things with it you do the inverse operation to it. (If it's multiplied-divide it and if it's squared-sqrare root it.) Whatever you do to one side of the equal sign, you must do to both sides.
 solve for r.
 because a/a=1

+/-  because
You can ignore the +/-, because Volume is positive.

Happy Calculating!!!
|
Linear-equations/59522: Find the equation for this line (1,4)(5,6) 1 solutions
Answer 40789 by funmath(2925) on 2006-11-02 21:36:36 (Show Source):
You can put this solution on YOUR website!Find the equation for this line (1,4)(5,6)
In order to find the equation for a line you need the slope and a point.
You don't have a slope, so we need to find it using the slope formula  , m=slope, (x1,y1) and (x2,y2) are given points.
(x1,y1)=(1,4) and (x2,y2)=(5,6)

Now we can use the point slope formula  ,m=slope, and (x1,y1) is a given point.
m=1/2 and (x1,y1)=(1,4)
 Slope intercept form of the line.
 Standard form of a line.
Happy Calculating!!!
|
Linear-systems/59501: Can someone help me solve the system by graphing it for me?
I have to send it through the computer.
x - 2y = 8
x + y = -1
Thank you so much,
Lyn 1 solutions
Answer 40773 by funmath(2925) on 2006-11-02 19:29:05 (Show Source):
You can put this solution on YOUR website!Hi Lyn,
Can someone help me solve the system by graphing it for me?
I have to send it through the computer.
L1) x - 2y = 8
L2) x + y = -1
For L1, let y=0 and solve for x
x-2(0)=8
x-0=8
x=8 Plot (8,0)
Now let x=0 and solve for y:
0-2y=8
-2y/-2=8/-2
y=-4 plot (0,-4)
Connect the points and you have this line.

For L2), let y=0 and solve for x
x+0=-1
x=-1 Plot (-1,0)
Let x=0 and solve for y
0+y=-1
y=-1 Plot (0,-1)
Connect the points and you have a second line:

They intercect at (2,-3)
Happy Calculating, Lyn!!!
|
Graphs/59492: Can someone help me on this problem?
I need to rewrite the equation 2x - 3 = -6 as a function of x
2X=3
Thank you,
Ashley 1 solutions
Answer 40767 by funmath(2925) on 2006-11-02 18:50:54 (Show Source):
You can put this solution on YOUR website!Hi Ashley,
I think you left off a y. Otherwise, without another variable we could not rewrite the equation as a function of x.
I'm adding a y.
Rewrite 2x-3y=-6 as a function of x.
Solve the equation for y:
-2x+2x-3y=-2x-6
-3y=-2x-6

Now y is a function of x. Y depend on what x is.
Happy Calculating, Ashley!!!
|
Expressions-with-variables/59488: Can someone help me with this problem?
Given f(x) = x^2 + 3x + 2, I need to find f(0).
Thank you,
sher 1 solutions
Answer 40763 by funmath(2925) on 2006-11-02 18:43:16 (Show Source):
You can put this solution on YOUR website!Hi Sher,
I saw your other questions on graphing inequalities. I don't think anyone can graph the inequalities. We can only graph the functions and tell you where we would shade if we could. If you want me to do those anyway, let me know. Otherwise, I'm leaving them for someone else in hopes that someone out there knows some computer commands that I don't.
:
Given  , I need to find f(0).
:
For this you just substitute 0 in for x and simplify:

:
Did you know that f(0) is the y intercept of the graph? This graph crosses the y axis at (0,2).
:
Happy Calculating, Sher!!! One More Week :-)
|
Functions/59471: Can someone please provide me with an example of a composite function step by step solution 1 solutions
Answer 40756 by funmath(2925) on 2006-11-02 18:30:50 (Show Source):
You can put this solution on YOUR website!Here's a problem set I did for someone else a couple of days ago. The last few are composite functions.
:
Use the functions  ,  , and  to find each of the following.
(1) (f + g) (-1)

:
(2) (g - f) (x)

:
(3) (fh)(0)

:
(4) (g o f) (-1)=g(f(-1))
f(-1)=2(-1)+7
f(-1)=-2+7
f(-1)=5
g(f(-1))=g(5)
g(5)=(5)^2+3(5)
g(5)=25+15
g(5)=40

:
(5) (f o f) (0)=f(f(0))
f(0)=2(0)+7
f(0)=0+7
f(0)=7
f(f(0))=f(7)
f(7)=2(7)+7
f(7)=14+7
f(7)=21

:
(6) (g/f) (4)

:
(7) (g o h) (1/2)=g(h(1/2))

g(h(1/2))=g(-2/13)

:
(8) (f o g o h) (8)=(fog)(h(8))

(fog)(h(8))=(fog)(1)=f(g(1))

f(g(1))=f(4)
f(4)=2(4)+7
f(4)=8+7
f(4)=15

:
Happy Calculating!!!
|
Linear-equations/59434: find the equation of the line through the two points (3,4) and (2,-1); write the equation in the slope intercept form and find the x and y intercept of the line.
Thank you! 1 solutions
Answer 40736 by funmath(2925) on 2006-11-02 14:51:35 (Show Source):
You can put this solution on YOUR website!Find the equation of the line through the two points (3,4) and (2,-1); write the equation in the slope intercept form and find the x and y intercept of the line.
:
In order to write the equation of a line, we need a point and a slope.
We don't have a slope, so we need to use the slope formula:  , m=slope, (x1,y1) and (x2,y2) are given points.
(x1,y1)=(3,4) and (x2,y2)=(2,-1)

Now we can find the equation of the line using the point-slope formula to find the equation of the line.  , m=slope, (x1,y1) is a point on the line.
m=5, (x1,y1)=(3,4)
 This is in slope intercept form:  , where m=slope and (0,b)=y-intercept.
The y-intercept is (0,-11)
To find the x-intercept, let y=0 and solve for x:

The y-intercept is (2.2,0)
In case you'd like to see the graph of the line for fun:

Happy Calculating!!!
|
Radicals/59417:  1 solutions
Answer 40734 by funmath(2925) on 2006-11-02 14:38:05 (Show Source):
You can put this solution on YOUR website! First factor the denominators and look for the lowest common denominator (LCD).
The LCD is: (x+2)(x-2) Notice that if x=-2 or 2 there will be 0 in 1 or more denominators. If we get those answers they are extraneous, or false solutions. Multiply each term by the LCD.

5(x+2)-5=1(x-2)
5x+10-5=x-2
5x+5=x-2
-x+5x+5=-x+x-2
4x+5=-2
4x+5-5=-2-5
4x=-7
4x/4=-7/4

Happy Calculating!!!
|
Money_Word_Problems/59428: This question is from textbook
Ms. Jordan has been given a loan of $2500 for 1 year. If the interest charged is $275, what is the interest rate on the loan? 1 solutions
Answer 40729 by funmath(2925) on 2006-11-02 14:13:33 (Show Source):
You can put this solution on YOUR website!Ms. Jordan has been given a loan of $2500 for 1 year. If the interest charged is $275, what is the interest rate on the loan?
:
The formula for simple interest is:  , I=interest, P=principle, rate=rate (in decimal), and t=time (in years)
:
P=2500
t=1
I=275
r=r (we don't know this yet)
:

If you need the interest rate in percentage, multiply it by 100%
r=.11(100%)=11%
:
Happy Calculating!!!
|
percentage/59431: During the basketball season,Pierre scored 25% more points than Jim. Pierre scored 220 points for the season. The number of points jim scored was 1 solutions
Answer 40727 by funmath(2925) on 2006-11-02 14:07:26 (Show Source):
You can put this solution on YOUR website!During the basketball season,Pierre scored 25% more points than Jim. Pierre scored 220 points for the season. The number of points jim scored was
Let the amount of points that Jim scored be: x
Then 25% of x is: (25/100)x=.25x
"More than" means add:
x+.25x=220
1.25x=220
1.25x/1.25=220/1.25
x=176
:
Happy Calculating!!!
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