Answer:
x = - 5, x = 2
Step-by-step explanation:
Using the rules of logarithms
log x - log y = log (
)
x = n ⇔ x = 
note that log x =
x
Given
log (x² + 3x) - log10 = 0, then
log(
) = 0, thus
=
= 1 ( multiply both sides by 10 )
x² + 3x = 10 ( subtract 10 from both sides )
x² + 3x - 10 = 0 ← in standard form
(x + 5)(x - 2) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 5 = 0 ⇒ x = - 5
x - 2 = 0 ⇒ x = 2
Solution is x = - 5, x = 2
Answer:
x = -2 and y = 2
Step-by-step explanation:
We have the following system of linear equations;
y=x+4
y=-2x-2
To solve the above system, we shall be equating the right hand sides of the two equations since we have y's on the left hand side of both equations;
x + 4 = -2x - 2
add 2x on both sides of the equation;
x + 4 + 2x = -2x - 2 + 2x
3x + 4 = -2
subtract 4 on both sides of the equation;
3x + 4 - 4 = -2 - 4
3x = -6
x = -2
We can use the first equation y=x+4 to determine the value of y;
y = -2 + 4
y = 2
The solution to the system of linear equations is thus;
x = -2 and y = 2
Answer:
24.83 hours
Step-by-step explanation:
Given that :
Let time taken by pumps be :
Pump A = 60 hours
Pump B = 80 hours
Pump C = 90 hours
Recall :
Rate = 1 / time taken
The rates of the pumps are :
Pump A rate = 1 / 60
Pump B rate = 1/80
Pump C rate = 1/90
Combined rate : 1/60 + 1/80 + 1/90
Combined rate = (12 + 9 + 8) / 720 = 29/720
Combined rate = 29/720
The time taken together will be :
1 / combined rate = 1/(29/720) = 720 / 29 = 24.827 hours
Hello!
You can solve this algebraically
7w < -42
Divide both sides by 7
w < -6
The answer is any number less than -6 or w < -6
Hope this helps!