Given:
GL = 4x + 1
LO = 6x - 3
GT = 17
TO = 21
To find:
The value of x.
Solution:
By the property of kite:
GL = GT and LO = TO
Take any one pair.
GL = GT
Subtract 1 from both sides.
Divide by 4 on both sides.
The value of x is 4.
This could be rephrased as:
You start with 100 grams of a substance. One year later you have 70 grams. What is the half-life?
We need this formula:
half-life = (time * natural log (2)) / natural log (beginning amount / ending amt)
half-life = (1 year * .69315) / natural log (100 / 70)
half-life = (.69315) / 0.35667494396
half-life = 1.9433661145 years
Rounding to nearest year half-life = 2 years
Sourse: https://www.1728.org/halflif2.htm
(See problem 3)
$37 times 0.07 is $2.59
Add the sales tax and total price and you will get $39.59
Good luck!