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Inequalities/64891: This question is from textbook Pre-Algebra
Find the sum or difference. -3/4 - (-5/18)
Thanks sooooooo much! Happy Holidays!
1 solutions
Answer 45372 by checkley71(8403)   on 2006-12-12 21:16:11 (Show Source):
You can put this solution on YOUR website!FIRST WE FIND A COMMON DENOMINATOR FOR 4 & 18 WHICH IS 36 (2*2)(2*9) SINCE A 2 IS COMMON TO BOTH DENOMINATORS WE ONLY NEED TO USE IT ONCE. ALL OTHER NUMBERS ARE MULTIPLIED TO GET THE NEW DENOMINATOR - THUS 2*2*9=36
-3/4=X/36
4X=-108
X=-108/4
X=-27 THUS WE HAVE -3/4=-27/36
-----------
5/18=X/36
18X=180
X=-180/18
X=-10 THUS WE HAVE -5/18=-10/36
-------------------------
-27/36-(-10/36)
-27/36+10/36
-17/36
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Rectangles/64884: Please help: The length of a rectangle is 4 feet less than twice the width of the rectangle. If the perimeter of the rectangle is 136 feet, find the length of the rectangle.
1 solutions
Answer 45369 by checkley71(8403) on 2006-12-12 21:07:56 (Show Source):
You can put this solution on YOUR website!LENGTH=2W-4 SO THE PERIMETER IS
2W+2(2W-4)=136
2W+4W-8=136
6W=136=8
6W=144
W=144/6
W=24 SOLUTION
THEN THE LENGTH IS 2*24-4=48-4=44
PROOF
2*24+2*44=136
48+88=136
136=136
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Equations/64893: what is the answer to using addition on #1 and #2 and on #3 using substituion
#1)x + 2y =5 #2)5x -4y =1 #3) 7x + y = 1
3x +4y =1 -10x + 8y = -3 3x + 2y= -9
1 solutions
Answer 45368 by checkley71(8403) on 2006-12-12 21:02:01 (Show Source):
You can put this solution on YOUR website!X+2Y=5
3X+4Y=1
-----------------
4X+6Y=6 ANSWER #1
######################################
5X-4Y=1
-10X+8Y=-3
-----------------
-5X+4Y=-2 ANSWER #2
#####################################
7X+Y=1
-(3X+2Y=-9)
-----------------
4X-Y=10 ANSWER #3
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Miscellaneous_Word_Problems/64898: Any help on this would be great, I can't seem to figure it out.
A photo is 3 inches longer that it is wide. A 2-inch border is placed around the photo making the total area of the photo and border 108in2. What are the dimensions of the photo?
1 solutions
Answer 45366 by checkley71(8403) on 2006-12-12 20:54:52 (Show Source):
You can put this solution on YOUR website!(X+4)(X+7)=108
(X+4)IS THE WIDTH (X)+ TWO 2 INCH BORDERS
(X+7)IS THE LENGTH (X+3)+ TWO 2 INCH BORBERS
(X+4)(X+7)=108
X^2+11X+28=108
X^2+11X-80=0
(X+16)(X-5)=0
X+16=0
X=-16 (NON SOLUTION)
X-5=0
X=5 SOLUTION. INCHES FOR THE WIDTH OF THE PICTURE
X+3=8 INCHES FOR THE LENGTH OF THE PICTURE.
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Inequalities/64889: This question is from textbook Pre-Algebra
Find the sum or difference. -4/17 + 3/5
Thanks soooooooooo much! Happy Holidays!
1 solutions
Answer 45363 by checkley71(8403) on 2006-12-12 20:40:14 (Show Source):
You can put this solution on YOUR website!-4/17+3/5 WE NEED TO FIND A COMMON DENOMINATOR FOR THESE 2 FRACTIONS THUS
17*5=105 WHICH IS COMMON.
NOW WE CONVERT BOTH FRACTIONS TO FRACTION WITH A DENOMINATOR OF 85
-4/7=X/105
7X=-4*105
7X=-420
X=-420/7
X=-60 SO -4/7 BECOMES -60/105
------------------------------------
3/5=X/105
5X=315
X=315/5
X=63 SO 3/5 BECOMES 63/105
------------------------------------
NOW WE CAN SUBTRACT THESE FRACTIONS
63/105-60/105=3/105=1/35
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Functions/64857: For the floor plans given in exercise 27, determine whether the side
through the points (2, 3) and (11, 6) is perpendicular to the side through the points
(2, 3) and (-3, 18).
1 solutions
Answer 45360 by checkley71(8403) on 2006-12-12 20:28:16 (Show Source):
You can put this solution on YOUR website!(6-3)/(11-2)=3/9=1/3 SLOPE
(18-3)/(-3-2)=15/-5=-3 SLOPE THAT IS PERPENDICULAR TO THE FIRST SLOPE BECAUSE IT IS THE NEGATIVE RECIPRICAL OF 1/3
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Functions/64860: Write the equation of the line passing through each of the given pairs of points. Write your
result in slope-intercept form, where possible.
(2, -3) and (2, 4)
1 solutions
Answer 45359 by checkley71(8403) on 2006-12-12 20:24:37 (Show Source):
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Expressions-with-variables/64873: This question is from textbook algebra 1
Determine the best method to solve the system .Then solve for x and y.
2x+y=3x-15
x+5=4y+2x
1 solutions
Answer 45354 by checkley71(8403) on 2006-12-12 20:07:58 (Show Source):
You can put this solution on YOUR website!2X+Y=3X-15
2X-3X+Y=-15
-X+Y=-15
-----------------------
X+5=4Y+2X
X-2X-4Y=-5
-X-4Y=-5
-----------------------
NOW WE CAN SUBTRACT THESE 2 EQUATIONS AND SOLVE OFOR X & Y.
-X+Y=-15
-(-X-4Y=-5)
-----------------------
5Y=-10
Y=-10/5
Y=-2 SOLUTION
NOW SUBSTITUTE (-2) FOR Y IN ONE OF THESE EQUATIONS
2X+(-2)=3X-15
2X-2=3X-15
-X=-15+2
-X=-13
X=13 SOLUTION
PROOF
13+5=4(-2)+2*13
18=-8+26
18=18
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Money_Word_Problems/64816: An experienced accountant can prepare a tax return in 10 hours. A novice accountant can do the job in 16 hours. How long will it take them to do the job working together?
1 solutions
Answer 45330 by checkley71(8403) on 2006-12-12 14:46:36 (Show Source):
You can put this solution on YOUR website!THIS IS A SIMPLE SOLUTION.
MAKE A FRACTION OF THE PRODUCT OF THE TIMES DIVIDED BY THE SUM OF THE TIMES THUS:
(16*10)/(16+10)
160/26=6.1538 HOURS TO DO THE JOB JOINTLY.
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Travel_Word_Problems/64818: Roberto invested some money at 7%, and then investes $5000 more than twice this amount at 11%. His total annual income from the two investments was $3450. How much was invested at 11%?
1 solutions
Answer 45329 by checkley71(8403) on 2006-12-12 14:42:00 (Show Source):
You can put this solution on YOUR website!.07x+.11(2x+5000)=3450
.07x+.22x+550=3450
.29x=3450-550
.29x=2900
x=2900/.29
x=10000 amount invested @ 7%
2*10000+5000=20000+5000=25000 amount invested @ 11%
proof
.07*10000+.11*25000=3450
700+2750=3450
3450=3450
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Graphs/64755: Find the slope of any line perpendicular to the line through points (0, 5) and
(-3, -4).
1 solutions
Answer 45315 by checkley71(8403) on 2006-12-12 10:29:10 (Show Source):
You can put this solution on YOUR website!(0,5)(-3,-4) developes the slope of
(y2-y1)/(x2-x1)
(-4-5)/(-3-0)
-9/-3=3 is the slope of a line through these 2 points.
for a perpendicular line it has to have a slope of -1/3 (this is a negative reciprical of the line with the slope of 3).
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Inequalities/64719: ok i need help with this problem:
1x+2y=2
-4x+3y=25
using the elimination process
1 solutions
Answer 45277 by checkley71(8403) on 2006-12-11 20:08:56 (Show Source):
You can put this solution on YOUR website!-4X+3Y=25 NOW MULTIPLY THE OTHER EQUATION BY 4 WE GET
4X+8Y=8 NOW ADD
--------------------------------------
11Y=33
Y=33/11
Y=3 SOLUTION
SUBSTITUTING 3 FOR Y WE GET
4X+8*3=8
4X+24=8
4X=-24+8
4X=-16
X=-16/4
X=-4 SOLUTION
PROOF
-4*-4+3*3=25
16+9=25
25=25
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Equations/64737: I need help with this...
Write the slope-intercept form of an equation of the line that passes through thr given point and is perpendicular to the graph of each equation.
(-2,-2), y= -1/3x+9
I got really confused in class today and my teacher explained how to do these problems in examples. Is there a formula i can use for it?
1 solutions
Answer 45273 by checkley71(8403) on 2006-12-11 19:39:38 (Show Source):
You can put this solution on YOUR website!Y=-1/X+9 IS A LINE WITH A SLOPE OF (-1/3) & A Y INTERCEPT OF (0,9).
FOR A LINE TO BE PERPENDICULAR IT MUST HAVE A SLOPE THAT IS THE NEGATIVE RECIPRICAL OF THE LINE IT IS PERPENDICULAT TO. THUS THE SLOPE IS 3 FOR THE PERPENDICULAR LINE THROUGH (-2,-2).
NOW SUBSTITUTE THESE POINTS X=-2, Y=-2 AND THE SLOPE IN THE LINE FORMULA
Y=mX+b WE GET
-2=3(-2)+b
-2=-6+b
B=-2+6
b=4 SOLUTION FOR THE Y INTERCEPT (0,4)
THUS THE EQUATION FOR THIS LINE IS
Y=3X+4
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Expressions-with-variables/64734: The sum of two numbers is 82. Their difference is 24. Write a system of equations that describes this situation. Solve by elimination to find the two numbers.
1 solutions
Answer 45271 by checkley71(8403) on 2006-12-11 19:33:45 (Show Source):
You can put this solution on YOUR website!X+Y=82
X-Y=24 NOW ADD THESE 2 EQUATIONS
--------------------------------------------
2X=106
X=106/2
X=53 SOLUTION
53+Y=82
Y=82-53
Y=29 SOLUTION
PROOF
53-29=24
24=24
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expressions/64696: This question is from textbook
can you explain to me step by step if I need to change the whole number into an improper fraction to work the problem
1 solutions
Answer 45263 by checkley71(8403) on 2006-12-11 18:42:09 (Show Source):
You can put this solution on YOUR website!7
-4 2/3 CHANGE THE 7 TO 6 3/3 THEN SUBTRACT THE FRACTIONS AND THE WHOLE NUMBERS THUS
6 3/3
-4 2/3
------------
2 1/3
-------------------------------------------------------------------
7=6 3/3 because 3/3=1 & 6+1=7
------------------------------------------------
7 also = 6 7/7 if you were working with fractions with 7 in the denominator
again 6+7/7=6+1=7
--------------------------------------------------------------------
7 also = 6 35/35 if you were working with fractions with 35 in the denominator
again 7=6+35/35=6+1=7
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Graphs/64698: This question is from textbook An Incremental Development
Find the equation of the line that passes through (3,-5) and is perpendicular to the line that passes through (7,-5) and (-2,-4)
1 solutions
Answer 45255 by checkley71(8403) on 2006-12-11 18:14:39 (Show Source):
You can put this solution on YOUR website!FIRST WE FIND THE SLOPE OF THE LINE THROUGH THE 2 POINTS THUS
(Y2-Y1)/(X2-X1)
(-4+5)/(-2-7)
1/-9 IS THE SLOPE OF THE LINE THROUGH ((7,-5)(-2,-4)
NOW TO IDENTIFY A LINE PERPENDICULAR TO THIS LINE IT HAS TO HAVE A SLOPE OF A NEGATIVE RECIPRICAL OF THIS SLOPE. THUS THE SL;OPE OF A LINE PERPENDICULAR TO THIS LINE THROUGH (3,-5) HAS A SLOPE OF 9. NOW WE SUBSTITUTE THESE X&Y POINTS IN THE FORMULA USING THE NEW SLOPE WE GET
-5=9*3+b
-5=27+b
b=-5-27
b=-32 THUS THUIS EQUATION IS
Y=9X-32
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