Ineed with this quick extra points and i’m marking brainlist to step by step explanation

Step-by-step explanation:

We have given two equations:

3x - y = 15

6x - 2y = 30

Consider A. (6,3)

Plug x= 6 and y = 3 in both the equations And see what we get:

3x - y = 15  

or 3×6 - 3 = 15

or 18 - 3 = 15

or 15 = 15 ,

And

6x - 2y = 30

or 6×6 - 2×3 = 30

or 36 - 6 =30

or 30 = 30

so this point (6,3) is the solution of system of equation  

Next, B. (7 , 6)

Again we do the same steps:

Plug x= 7 and y = 6 in both the equations

3x - y = 15

or 3×7 - 6 = 15

or 21 - 6 = 15

or 15 = 15

And

6x - 2y = 30

or 6×7 - 2×6 = 30

or 42 - 12 =30

or 30 = 30

The point (7,6) is the solution of system of equation

Next, C. (8,9)

Plug x=8 and y =9 in both the equations

3x - y = 15

or 3×8 - 9 = 15

or 24 - 9 = 15

or 15 = 15

And

6x - 2y = 30

or 6×8 - 2×9 = 30

or 48 - 18 =30

or 30 = 30

The point (8,9) is also the solution of system of equation

Hence all the points (6,3),(7,6) and (8,9) are the solution of given system of equations.

1,407.5 hours

step-by-step explanation:

we first convert all the time to hours and then sum them up.

there are 24 hours in 1 day, in 58 days, there are 24 x 58 = 1,392 hours.

there are 60 minutes in 1 hour, thus, 30 minutes will be equivalent to 30 / 60 = 0.5 hours.

therefore, the number of hours it will take mercury to complete a full rotation is 1,392 + 15 + 0.5 = 1,407.5 hours

take the logarithm of both sides (the base of the log doesn't matter):

apply the exponent property - this says that :

distribute the log terms on both sides:

group like terms together:

divide through both sides by the coefficient on :

you can do some additional rewriting here using the properties of the logarithm to simplify things if you like: