2007-07-23 15:38:39 · 5 answers · asked by Martinez 1 in Science & Mathematics ➔ Mathematics
6 x + 30 = 16 x
10 x = 30
x = 3
2007-07-23 22:09:29 · answer #1 · answered by Como 7 · 0⤊ 0⤋
2/5 + 2/x = 16/15. Put things in the left-hand side together, LCD = 5x, so
2x/5x + 10/5x = 16/15, or
(2x +10)/5x = 16/15. Cross multiply, or
15(2x+10) = 16(5x) or
30x + 150 = 80x, gather like terms
150 = 50 x, so x = 3.
CHECK:
2/5 + 2/3 =? 16/15. LCD on left is 15, so
2*3/15 + 2*5/15
6/15 + 10/15
16/15.
done.
2007-07-23 22:44:08 · answer #2 · answered by pbb1001 5 · 0⤊ 0⤋
Hmm, let's see...
2/5 + 2/x = 16/15 is the same as
6/15 + 2/x = 16/15=
6/15 + 10/5x = 16/15=
6/15 + 10/(15/5) = 16/15
so x=3
2007-07-23 22:46:15 · answer #3 · answered by Anonymous 3 · 0⤊ 0⤋
2/5 + 2/x = 16/15
2/x = 16/15 - 2/5
2/x = 16/15 - 6/15
2/x = 10/15
2/x = 2/3
2x = 3*2
x = 3
2007-07-23 22:43:06 · answer #4 · answered by fofo m 3 · 0⤊ 0⤋
To find the LCD in this equation, look at the three denominators, and find the smallest number that is 'evenly divisble' by each of the denominators.
15x does the trick.
15x is divisible by 5, by x AND by 15
Multiply each term in the equation by 15x, cancelling as you go ... leaving ...
15x*(2/5) + 15x*(2/x) = 15x*(16/15)
6 + 30 = 16x
solve from there
2007-07-23 22:47:48 · answer #5 · answered by mathgoddess83209 3 · 0⤊ 0⤋