Answer:
30
Step-by-step explanation:
First, find out how many half-lives have passed. Divide the number of minutes by the length of a half-life.
20÷10=2
2 half-lives have passed.
Now figure out how much nitrogen will be left after 2 half-lives have passed. Multiply the starting amount of nitrogen by
1/2
a total of 2 times.
120x1/2 1/2=30
That calculation could also be written with exponents:
120x(1/2)2=30
After 2 half-lives, the amount of nitrogen left will be 30 grams.
and the length is
Answer:
width=6cm, lenth is 7cm
Step-by-step explanation:
Let width of rectangle be x cm
Twice width=2x cm
length=2x-5 cm
Area of the rectangle= L× W =42cm²
(2x-5) × x =42
x(2x-5)=42
2x²-5x-42=0
solving the quadratic equation
x=6cm
width=6cm
length= (2×6)- 5 =7cm
What is the length?
The answer is 700 because you just do 14×5 then, you add a zero at the end.
Hope I Helped!!!!!!!
=)=)=)=)=)
(y•40)+(y•8)
Solve for the entities in the parenthesis
= 40y + 8y
Add like terms
= 48y
This should be your answer, but let me know if it wasn't what you needed, thanks!