So
-4x-5y-z=18
-2x-5y-2z=12
-2x+5y+2z=4
the 2 last equations look perfect for canceling each other so add them together
-2x-5y-2z=12
<u>-2x+5y+2z=4 +</u>
<u />-4x+0y+0z=16
-4x=16
divide both sides by 4
-x=4
multiply -1
x=-4
now we have
-4x-5y-z=18
-2x+5y+2z=4
add them together
-6x+0y+z=22
but x=-4 so
-6(-4)+z=22
24+z=22
subtract 24 from both sides
z =-2
subsitute into any equation
-2x-5y-2z=12
x=-4
z=-2
-2(-4)-5y-2(-2)=12
8-5y+4=12
12-5y=12
subtract 12 from both sides
-5y=0
y=0
x=-4
y=0
z=-2
He is going 12.5 kilometers per hour.
or 12.5 kph
or 12 1/2 kph
Sometimes, because if you have a negative number than the opposite is positive and more. Then if you have a positive number it will be negative and therefore less.
Let the number of men and the number of women in the beginning be x and y
Now,
Now, In 2nd case,
No. Of men=x-63 and no. Of women =y-12
Now,the ratio becomes
Now,we have, 2x=5y
Putting the value of Y=56 in 2x=5y,we get,

Hence, the number of men was 140 and the no. of women was 56
Hi...I am from India.. Where are you from?
Answer:
the solution set is -11 > 1 + a?
a > -10
a -12
a < -10