One place I found said to add 1 to both sides of the fraction, another says to mulitify it has me all confused?
2007-03-10 16:30:04 · 11 answers · asked by DONNA T 3 in Science & Mathematics ➔ Mathematics
2x/3 + 4x/8 = 15
24(2x/3) + 24(4x/8) = 24(15)
16x + 12x = 360
28x = 360
28x/28 = 360 / 8
x = 360/28
x = 90/7
x = 12.85714286
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2007-03-11 04:16:16 · answer #1 · answered by SAMUEL D 7 · 1⤊ 0⤋
find a common denominator on the left side. it's 24 (which you find from 8 times 3). Therefore:
(2/3)x would be multiplied by 8 and become (16/24)x
and (4/8)x would be multiplied by 3 and become (12/24)x.
Then add the new "like" fractions:
(16/24)x + (12/24)x = (28/24)x
Then solve the equation for x by multiplying the right side by the reciprocal of the left side:
x = 15 * (24/28) = .....
and whatever you get is your answer.
Hope this helps.
2007-03-10 16:46:12 · answer #2 · answered by Anonymous · 0⤊ 0⤋
I think multiplying is what you want (or multify, if you like ;)
2x/3 + 4x/8 = 15
Multiply both sides by both denominators (the fractions' bottoms):
x3 gives you:
2x + 12x/8 = 45
x8 then gets you:
16x + 12x = 360
simplify by adding:
28x = 360
then divide by 28:
x = 360/28
x = 90/7
x = 12 6/7
"What do you think, sirs?"
Barjesse37
2007-03-10 16:47:37 · answer #3 · answered by barjesse37 3 · 0⤊ 0⤋
a million) 15m+3=-12 15m=-15 m=-a million 2)3/2 x= 3 3x=6 x=2 3)-7x= -15/2 - 6/2 -7x=-21/2 -14x= -21 14x = 21 x = 3/2 4) 4x + 6x + a million=3 10x+a million = 3 10x = 2 x= a million/5 5) 3/2 x + 12 =6x 12= 9/2 x 24 = 9x x= 24/9 x= 8/3
2016-11-24 19:49:30 · answer #4 · answered by ? 4 · 0⤊ 0⤋
First put 2x/3 and 4x/8 on the common denominator and add them:
you get:
2x/3+4x/8=(16x+12x)/24
=28x/24
=7x/6
then equate to 15:
7x/6=15
7x=15*6
7x=90
x=90/7
2007-03-10 16:43:14 · answer #5 · answered by Roger Aime 2 · 0⤊ 0⤋
Multiply through by 24. (3 * 8 = 24, the LCM of 3 & 8)
16x + 12x = 360
28x = 360
x = 360/28 = 90/7
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Only "add 1 to both sides" if there's a REASON to do so!! Be careful about reading and trying apply "formulas", etc. to other problems without UNDERSTANDING what you're reading. It is VERY good that you're trying to learn by reading, just try to understand a principle before applying it!
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2007-03-10 16:33:36 · answer #6 · answered by RockHanger 3 · 0⤊ 0⤋
mutiply 2x/3 by 8 and 4x/8 by 3
2x/3 x 8= 16x/24
4x/8 x 3= 12x/24
add both answer= 28x/24
therefore 28x/24=15
28x=15x24
x=360/28
2007-03-10 16:45:42 · answer #7 · answered by jos3308 2 · 1⤊ 0⤋
U should do it like this:
2x/3 + 4x/8 = 15
x(2/3 + 1/2) = 15
x (7/6) = 15
x = 15 /(7/6)
x = 15(6/7)
x = 30/7
2007-03-10 16:39:32 · answer #8 · answered by wintersun_elyse 1 · 0⤊ 1⤋
16x+12x=360
28x=360
x=360/28 or 12 6/7
2007-03-10 17:59:01 · answer #9 · answered by lance_nhoj 2 · 0⤊ 0⤋
find the LCD which is 24
16x/24 + 12x/24 = 15
28x/24 = 15
28x = 360
x = 90/7
2007-03-10 16:42:27 · answer #10 · answered by Ha!! 2 · 0⤊ 0⤋