Answer:
x = -1, y = 2 and z = 1
Step-by-step explanation:
The given system of equations are :
2x - y + 3z= -1 ....(1)
x + 2y - 4z = -1 ......(2)
y – 2z = 0 .....(3)
Equation (3) can be written as :
y = 2z
Use y = 2z in equation (2)
x + 2(2z) - 4z = -1
x + 4z - 4z = -1
x = -1
Put the value of x in equation (1) :
-2 -y +3z = -1
-y+3z = 1 ....(4)
Adding equation (3) and (4)
y-2z+(-y+3z)=1
z = 1
Now put z = 1 in equation (4)
-y+3=1
-y = -2
y = 2
Hence, the values of x,y and z are -1, 2 and 1 respectively.
Given :
Xanthe and Sarah together raised $302 .
If Xanthe raised $102 more than Sarah .
To Find :
The amount raised by Sarah .
Solution :
Let , amount raise by Sarah is x .
So , by the relation given , price raised by Xanthe is 102 + x .
Now , sum of their amount raised is :

Therefore , the amount raised by Sarah is $100 .
Hence , this is the required solution .
Speed of the ship in the second hour = (62.5 * x ) / 100 kph.
In third hour it is [(62 * x) / 100 ] * x/100]
is 4th hour its is the above * x/100 again so we can now form the equation
62.5x x x
------- * ---- * ---- = 32
100 100 100
62,5 x^3 = 32,000,000
x^3 = 512,000
x = 80 <----- Answer to (a)
(b) Ship travels 62.5 in first hour then this falls by a common ratio of 0.8 each hour so we have a geometric sequence
Dist travelled in 6 hours = a1 1 - r^n
-------- = 62.5* (1 - 0.8^6) / 1 -0.8 = 230.56
1 - r
Answer is 230.56 km
Answer:
3m+m^2
Step-by-step explanation:
Given:
Karen earns $54.60 for working 6 hours.
Amount she earns varies directly with the number of hours she works.
She need to work to earn an additional $260.
To find:
Number of hours she need to work to earn an additional $260.
Solution:
Let the amount of earnings be A and number of hours be t.
According to question,

...(i)
where, k is constant of proportionality.
Karen earns $54.60 for working 6 hours.

Divide both sides by 6.


Put k=9.1 in (i).

Substitute A=260 in the above equation.

Divide both sides by 9.1.



Therefore, she need to work extra about 29 hours to earn an additional $260.