Answer:
1 x=-2.5 y = -5.5
2. x=5 y=1
Step-by-step explanation:
1) What is the solution of the given system?
5x-y=-7
3x-y=-2
Multiply the second equation by -1
-1*(3x-y)=-1(-2)
-3x +y = 2
Now add the first equation to the modified second equation
5x-y=-7
-3x +y = 2
------------------
2x = -5
Divide each side by 2
2x/2 = -5/2
x = -2.5
Now we need to find y
-3x+y =2
-3(-2.5) +y =2
7.5 +y =2
Subtract 7.5 from each side
7.5 -7.5 +y =2-7.5
y = -5.5
2) what is the solution of the given system?
5x+7y=32
8x+6y=46
Divide the second equation by 2
8x/2+6y/2=46/2
4x+3y =23
Multiply the first equation by 4
4 (5x+7y)=32*4
20x+28y = 128
Now multiply the modified 2nd equation by -5
-5(4x+3y )=-5(23
)
-20x -15y = -115
Lets add the new equations together to eliminate x
20x+28y = 128
-20x -15y = -115
---------------------
13y = 13
Divide each side by 13
13y/13 =13/13
y=1
Now substitute back in to find x
5x+7y=32
5x +7(1) =32
5x +7 =32
Subtract 7 from each side
5x+7-7 =32-7
5x =25
Divide by 5
5x/5 =25/5
x=5
X^2 = 7^2 + 24^2x^2 =49 + 576x^2 = 625
x = 25
Answer:
20 rands/kg
130,000 kg
Step-by-step explanation:
The equilibrium quantity and price are the solution to the system of equations ...
p = 120 -0.7q
p = 3 + 0.2q
Setting these equal, we get ...
0.2q +3 = p = -0.7q +120
0.9q = 117 . . . . . . . add 0.7q-3 to both sides
q = 117/0.9 = 130
p = 3 +0.2·130 = 29
The equilibrium price of maize meal is 29 rands per kg; the market equilibrium quantity is 130,000 kg.
9514 1404 393
Answer:
C- (14, 4); The vertex represents the maximum profit.
Step-by-step explanation:
The leading coefficient of the quadratic function is negative, so the graph opens downward, and the vertex represents a maximum.
The maximum value is at ...
x = -b/(2a) = -28/(2(-1)) = 14
f(14) = -14^2 +28(14) -192 = 4
The vertex is (14, 4). It represents the maximum profit.
