also what are three consecutive numbers whose sum is 60? could you please explain?
2007-06-26 11:19:10 · 19 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
=3x+15 = 4x
-1x = -15
x=15
19+20+21 = 60
2007-06-26 11:22:45 · answer #1 · answered by Sharp Marble 6 · 0⤊ 0⤋
1.) 3(x + 5) = 4x
~> 3x + 15 = 4x
-3x = -3x
~> 15 = x or x = 15
2.) You DONT know what the first of the three consectv #'s are... so you call that first one "x". The NEXT consecutive number will be "x + 1" right? And the one after that would be "x +2", you get it?
Add them all together for a sum of 60 get you the following:
x + (x+1) + (x+2) = 60 Then just do the algebra:
~~> x + x + 1 + x + 2 = 60
~~> 3x + 3 = 60
~~> 3x = 57 ~~> x = 19
The first # is 19, the 2nd # is therefore 20, and the 3rd # is 21
2007-06-26 18:27:10 · answer #2 · answered by The cat 3 · 0⤊ 0⤋
Multiply the left side out: 3x + 15 = 4x. Subtract 4x from each side: -x + 15 = 0. Subtract 15 from each side:
-x = -15 and multiply both sides by -1, to get x = 15
Oh, and those 3 numbers: let them be x, x+1 and x+2. Then x + (x+1) + (x+2) = 60; combining, you get 3x +3 = 60, 3x = 57 so x = 19 and the next two are then 20 and 21.
2007-06-26 18:21:54 · answer #3 · answered by Mark S, JPAA 7 · 0⤊ 0⤋
3(x+5) = 4x
3x+15 = 4x
-3x -3x
15 = x
the three whole consecutive numbers when added are,
19 + 20 +21 = 60
or the three consecutive whole numbers when multiplied in any order is,
3 * 4 * 5 = 60
2007-06-26 18:35:00 · answer #4 · answered by harold. 4 · 0⤊ 0⤋
3(x+5)=4x
Expand the brackets: 3x + 15 = 4x
Minus 3x from both sides: 15 = x
x is 15.
For the 3 consecutive numbers:
60 - 3(for the 3 numbers) = 57
57 divided by 3 = 19
so you have 19, 19, 19 plus 3.
u leave the 1st 19, add 1 to the 2nd, 20 and add 2 to the 3rd, 21
so its 19, 20, 21
19 + 20 + 21 = 60.
2007-06-26 18:32:08 · answer #5 · answered by Anonymous · 0⤊ 0⤋
3(x+5)=4x
3x+15=4x
15=x
Three consecutive numbers whose sum is 60 are 19, 20, and 21. Consecutive numbers are just whole numbers that are seperated by 1. You can find this for anything by dividing by three (or whatever the amount of consecutive numbers you need is) and using the same amount of numbers higher and lower.
2007-06-26 18:26:37 · answer #6 · answered by shmux 6 · 0⤊ 0⤋
3(x + 5) = 4x
3x + 15 = 4x
-3x + 3x + 15 = 4x - 3x
15 = x
Three consecutive numbers whose sum is 60:
this means what 3 numbers in order add up to 60
19 + 20 + 21 = 60
SO: 19, 20, 21
2007-06-26 18:49:49 · answer #7 · answered by A 4 · 0⤊ 0⤋
Rewrite as: 3x+15=4x
-4x+3x= -15
-x= -15 multiplying each side by -1, you get
x=15
Let x= the 1at number
x-1= the 2nd #, and x=2 = 3rd number, so:
x + ( x+1) + (x+2)=60
3x +3= 60 or 3x=57, and x=19
the second #= 19+1 =20, the 3rd # 19+2= 21
Your numbers are 19,20, and 21.
2007-06-26 18:31:37 · answer #8 · answered by WC 7 · 1⤊ 0⤋
Is this your homework? If you're going to cheat, just Google "algebra calculator", don't ask us. Most of those will give you the work anyways. Go to my source for the algebra question. Three consecutive numbers that add up to 60 are 19, 20, and 21. That's not even hard. You just divide 60 by three, then subtract 1 and add one.
2007-06-26 18:31:58 · answer #9 · answered by thedeej3269@sbcglobal.net 1 · 0⤊ 0⤋
3(x+5) = 4x
3x + 15 = 4x
3x - 4x = -15
-x = -15
x = 15
three consecutive numbers whose sum is 60 = 19, 20, 21
2007-06-26 18:24:45 · answer #10 · answered by drea 2 · 0⤊ 0⤋
60/3=20 twenty must be the middle consecutive +1 and -1 cancel out to find the average. 19 20 21
3(x+5)=4x : 3x+15=4x to simplify: to issolate x on one side of equasion to solve:15=X
2007-06-26 18:32:17 · answer #11 · answered by Checkered Square 3 · 0⤊ 0⤋