Answer:
(3,6)
Step-by-step explanation:
Collect like terms
y -5x = -9
y + 2x = 12
Using elimination method
Subtract equation 2 from equation 1
y - 5x = -9
y + 2x = 12
---------------
0. -7x = -21
Divide both sides by -7
-7x = -21
---- -----
-7 -7
x = 3
Substitute x=3 into equation 1
y = 5(3) - 9
y = 15 - 9
y = 6
Solution is (x,y) = (3,6)
Answer: The least number of minutes that he has used his phone in a month is 1248
Step-by-step explanation:
Let m represent the number of minutes that he used his phone in a month.
For his phone service, Michael pays a monthly fee of $16, and he pays an additional $0.04 per minute if use. This means that if he used m minutes in a month, the total cost would be
16 + 0.04m
The least he has been charged in a month is $69.52. This means that
16 + 0.04m ≥ 65.92
0.04m ≥ 65.92 - 16
0.04m ≥ 49.92
m ≥ 49.92/0.04
m ≥ 1248 minutes
Answer:
167.27 mg.
Step-by-step explanation:
We have been given that the half-life of Radium-226 is 1590 years and a sample contains 400 mg.
We will use half life formula to solve our given problem.
, where N(t)= Final amount after t years, 
= Original amount, t/2= half life in years.
Now let us substitute our given values in half-life formula.
Therefore, the remaining amount of Radium-226 after 2000 years will be 167.27 mg.
Answer:
Division property
Step-by-step explanation:
The property which states that we can divide both side of the equation by the same non-zero number is called the division property of equality.
The goal of dividing an equation is to isolate the unknown variable on one side.
For example, let the equation be:
2×x=10
Since the unknown variable x is being multiplied by the number 2, to isolate the variable an inverse operation needs to be applied - division:
2×x<u>÷2</u>=10<u>÷2</u>
<u />
Careful! Never forget to write the same operation on both sides of the equation! When doing so, the solution of the equation stays the same, i.e. we get an equivalent equation.
A ?
Might wanna double check though
