How would you solve these problems?
-3x<21
3+5x<18
-5y>13
Thank You
Hello-Please help me with some questions-Thank you?
2008-04-13 4:23 pm
回答 (8)
2008-04-13 4:49 pm
✔ 最佳答案
1) Divide both sides by -3-3x/-3 < 21/-3 (Don't forget to switch signs!)
Solve for x
x > -7
2) Subtract both sides by 3
3-3+5x < 18-3
Substitute
5x < 15
Divide both sides by 5
5x/5 < 15/5
Solve for x
x < 3
3) Divide both sides by -5
-5y/-5 > 13/-5 (Don't forget to switch signs!)
Solve for y
y < -13/5 or 2 3/5
Hope that helps!
2008-04-13 11:31 pm
1)
-3x < 21
x > 21/-3
x > -7
2)
3 + 5x < 18
5x < 18 - 3
x < 15/5
x < 3
3)
-5y > 13
y < 13/-5
y < -2 3/5 (-2.6)
-3x < 21
x > 21/-3
x > -7
2)
3 + 5x < 18
5x < 18 - 3
x < 15/5
x < 3
3)
-5y > 13
y < 13/-5
y < -2 3/5 (-2.6)
2008-04-13 11:29 pm
- 3x < 21
x > - 7
3 + 5x < 18
5x < 15
x < 3
- 5y > 13
y < - 13/5
x > - 7
3 + 5x < 18
5x < 15
x < 3
- 5y > 13
y < - 13/5
2008-04-14 12:27 am
-3x<21
3+5x<18
-5y>13
...............???? u have big problem here ...
-3x - 21 < 0
5x +3 -18<0
.........................
-5y -13> 0
......................
so.
-3x - 21 < 0
5x +3 -18<0
=====>
-3x - 21 < 0
5x -15 < 0 +
.........................
2x - 36 <0 =
x < 18..........................................1
and for -5y -13> 0 ===>
-5y > 13
y > -13/5
thats all
i hopp this help u
3+5x<18
-5y>13
...............???? u have big problem here ...
-3x - 21 < 0
5x +3 -18<0
.........................
-5y -13> 0
......................
so.
-3x - 21 < 0
5x +3 -18<0
=====>
-3x - 21 < 0
5x -15 < 0 +
.........................
2x - 36 <0 =
x < 18..........................................1
and for -5y -13> 0 ===>
-5y > 13
y > -13/5
thats all
i hopp this help u
2008-04-13 11:34 pm
-3x < 21
-x < 21/3
-x < 7
x > -7
3+5x < 18
5x < 15
x < 3
therefore -7 < x < 3
-5y > 13
-y > 13/5
y < -13/5
-x < 21/3
-x < 7
x > -7
3+5x < 18
5x < 15
x < 3
therefore -7 < x < 3
-5y > 13
-y > 13/5
y < -13/5
2008-04-13 11:30 pm
for every one you want to get x or y all by itself
the first one-all you do is divide by three, and since you are dividing by a negative switch the less then to greater then, x>-7
for the second one-subtract the three from both sides, 5x<15, then divide by 5 and get x<3
last one-divide by -5 and since its a negative switch the sign, y<-13/5
hope this helped
the first one-all you do is divide by three, and since you are dividing by a negative switch the less then to greater then, x>-7
for the second one-subtract the three from both sides, 5x<15, then divide by 5 and get x<3
last one-divide by -5 and since its a negative switch the sign, y<-13/5
hope this helped
2008-04-13 11:28 pm
x=21/3
x=7
8x=18
18/8=x=9/4
y=13/5
y=2.6
x=7
8x=18
18/8=x=9/4
y=13/5
y=2.6
2008-04-13 11:27 pm
-3x < 21
divide both sides by 3
-x < 7
x > -7
3+5x < 18
5x < 15
x < 3
-5y > 13
-y > 13/5
y < -13/5
divide both sides by 3
-x < 7
x > -7
3+5x < 18
5x < 15
x < 3
-5y > 13
-y > 13/5
y < -13/5
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