Answer:
(x - 4)² - 11
Step-by-step explanation:
Given
x² - 8x + 5
To obtain the required form use the method of completing the square.
add/subtract ( half the coefficient of the x- term)² to x² - 8x
= x² + 2(- 4)x + 16 - 16 + 5
= (x - 4)² - 11
Answer:
Net power = 20kW
B.) $128
Step-by-step explanation:
Given that :
Coefficient of performance = 2.5
Rate = 20kW
The net power required to operate the heat pump :
Energy delivery rate / Coefficient of performance
= 20kW / 2.5
= 8kW
B.) Given that electricity cost equals $0.08 per kW
If pump operates for 200 hours
Total energy used in kWhr :
8kW * 200= 1600kW
Cost per kW = $0.08
1600 * 0.08 = $128
Substitution would be a great approach to solving this system, because the first equation defines y as x - 10 and you can thus substitute x - 10 for y in the second equation:
2x + (x - 10) = 4
Then 3x - 10 = 4, and 3x = 14. Solving for x: x = 14/3.
Since y = x-10, subst. 14/3 for x to find y: y = 14/3 - 30/3 = -16/3
The solution is (14/3, -16/3).
The difference between every two adjacent members of the series is constant and equal to 6.
Answer:
B. 70°
Step-by-step explanation:
If this is an equilateral triangle, then each angle is 180/3 = 60
<A = 60 = x+3x+2x
60 = 6x
60/6 = 6x/6
10 =x
Angle B will also equal 60 degrees
BDA + x + B = 180
BDA + 10 + 60 = 180
BDA + 70 = 180
BDA = 180-70
BDA = 110
BDA and y are complementary angles since they form a straight line
BDA + y = 180
110 +y =1 80
y = 180-110
y = 70