Find the value of x
By the way the / means divide
a) (3x-1)/7=2
b) 4/7(6x+5)=0
c) (16-5x)/8 - (4(2x+5))/5=-2
d) (x+3)/2 + (x+2)/3=4/3
Preferably show your working too.
Thx.
2007-03-03 20:18:38 · 12 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
There are the answers you need get. Now, do your homework.
a) (3x-1)/7=2 >>>>>>>>>>>>> x=5
b) 4/7(6x+5)=0 >>>>>>>>>>>> x=-5/6
c) (16-5x)/8 - (4(2x+5))/5=-2 >> x=0
d) (x+3)/2 + (x+2)/3=4/3 >>>>> x=-1
2007-03-03 20:30:55 · answer #1 · answered by diamond 3 · 1⤊ 0⤋
a) (3x-1)/7=2
3x - 1 = 2(7)
3x - 1 = 14
3x = 14 + 1
3x = 15
x = 15/3
x = 5
b) 4/7(6x+5)=0
6x + 5 = 0
6x+5= 0
6x = -5
x = -5/6
c) (16-5x)/8 - (4(2x+5))/5=-2
(the LCM of 8 n 5 is 40, multiply with whole eq.)
40(16-5x)/8 - 40(4(2x+5))/5= 40(-2)
5(16-5x) - 8(4(2x+5)) = -80
80-25x-8(8x+20)=-80
80-25x-64x+160=-80
-25x-64x= -80-80-160
-89x = -320
x = -320/-89
d) (x+3)/2 + (x+2)/3=4/3
(the LCM of 2,3,3 is 6, multiply this with whole eq.)
6(x+3)/2 + 6(x+2)/3 = 6(4/3)
3(x+3) + 2(x+2) = 2(4)
3x+9 + 2x + 4 = 8
3x+ 2x = 8-4-9
5x = -5
x = -5/5
x = -1
2007-03-04 04:43:28 · answer #2 · answered by ali k 2 · 0⤊ 0⤋
a) (3x-1)/7=2
3x-1=14
3x=15
x=5
b) 4/7(6x+5)=0
6x+5=0
6x=-5
x=-5/6
2007-03-04 04:45:21 · answer #3 · answered by Oni 2 · 0⤊ 0⤋
a)
(3x-1)/7=2
3x-1=14
3x=15
x=5
b)
4/7 (6x+5)=0
6x+5=0
6x= -5
x= -5/6
c)
(16-5x)/8 - (4(2x+5))/5= -2
(16-5x)/8 -( 8x+20)/5= -2
[5(16-5x) - 8(8x+20)]/40 = -2
80 - 25x - 64x - 160 = -80
-89x - 80 = -80
-89x = 0
x=0
d)
(x+3)/2 + (x+2)/3 = 4/3
[3(x+3) + 2(x+2)]/6 = 4/3
(3x+9+2x+4)/6 = 4/3
(5x+13)/6 = 4/3
5x+13 = (6)4/3
5x+13 = 24/3
5x+13 = 8
5x= -5
x= -1
2007-03-04 07:17:31 · answer #4 · answered by reza 2 · 0⤊ 0⤋
a) first times both sides by 7
3x-1=14
3x=15
x-5
b)For the next one
6x+5=0 so x=-5/6
c and d)
You have to make sure they have a common denominator
eg for d) 3(x+3)/6+2(x+2)/6=4/3
2007-03-04 04:38:43 · answer #5 · answered by LMS 3 · 1⤊ 0⤋
a)
(3x-1)/7 = 2 (x7)
3x - 1 = 14 (+1)
3x = 15 (/3)
x = 5
But I think you should work out the last 3, they're not that difficult and you should apply what you've been learning in lessons to your homework. Or you're never going to get anywhere in exams.
Lorna
2007-03-04 04:26:57 · answer #6 · answered by ? 6 · 1⤊ 0⤋
yes. i think almost anyone can.
q. 1 is 5. thats all im helping with cos this is stupid.
how old are u?
shammmeee ooonnn yyyoooouuu
2007-03-04 04:24:15 · answer #7 · answered by barbedwireribbons 3 · 1⤊ 1⤋
can you use yahoo answers at exam?
so dont get used to it for your homework!
these are not that difficult.
2007-03-04 04:38:21 · answer #8 · answered by abdosdt 3 · 2⤊ 0⤋
Sure, lots of people can. Anything else you want to know?
2007-03-04 04:21:28 · answer #9 · answered by thezaylady 7 · 1⤊ 1⤋
if ur smart eniugh to come to yahoo answers for ur homwork..ur smart enuf to solve em!
2007-03-04 04:25:02 · answer #10 · answered by Anonymous · 1⤊ 1⤋