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.
Answer:
candles = $400
matches = $20
Step-by-step explanation:
Let cost of candles = $c
Let cost of matches = $m
c = 20 m (20 times m)
c + m = 420
20m + m = 420
21 m = 420
m = 20
c = 20 (20) = 400
Answer
Step-by-step explanation:
The answer would be y=-x-3. 3x+3y=-9 is in standard form and you want it to be in y=mx=b form (slope-int) so subtract 3x by both sides. Now, you have 3y=-3x-9. Divide 3 to both sides, now you will get y=-x-3.
The answer is 253 square feet