Answer:
(14, -2)
Step-by-step explanation:
To solve by using substitution, begin by solving for a variable in the first equation. Let's solve for x:

Now we know what <em>x</em> equals. Let's substitute this into the second equation:

We can then simplify:
Given equation
Combine y terms
Add 2
Divide by -11
So, we now know the value of y = -2.
To find the value of X, we can substitute the value of Y into one of the equations. Let's use the first one:

Substitute for y
Distribute 8
Add 16
So, we now know the value of x = 14.
Therefore, we know a solution to the system of equations is (14, -2).
-4
Step-by-step explanation:
-4 show the number of wveryshaoaknd
21 is the right answer goodluck
Answer:
It will take 7 years ( approx )
Step-by-step explanation:
Given equation that shows the amount of the substance after t years,

Where,
= Initial amount of the substance,
If the half life of the substance is 19 years,
Then if t = 19, amount of the substance =
,
i.e.



Taking ln both sides,



Now, if the substance to decay to 78% of its original amount,
Then 


Again taking ln both sides,



Hence, approximately the substance would be 78% of its initial value after 7 years.
Answer:
Hello!!
If Sonny has $75 to spend and the purchase he would like to make requires $93. If he borrows extra money, he would need to borrow <u>$18</u> dollars.
Step-by-step explanation:

Hope this helps!!