<span>60.5 milligrams per square centimeter
First, determine how many half lives have expired by dividing the time by the half-life. So:
55/20 = 2.75
That means that only 2^(-2.75) = 0.148650889 = 14.8650889% of the original substance remains. So just divide the amount remaining by 0.148650889 to get the original amount.
9 / 0.148650889 = 60.5445419
So originally, there was 60.5 milligrams per square centimeter 55 years ago.</span>
Answer:
x=20
Step-by-step explanation:
This is a right triangle, so we can use the pythagorean theorem to help us find x.
The the theorem states that the sum of the legs squared is equal to the length of the hypotenuse squared.
Thus, our equation is:
x^2+48^2=52^2
Simplify.
x^2+2304=2704
Subtract 2304 from both sides.
x^2=400
Find the square root of both sides.
x=20
Answer:
180
Step-by-step explanation:
<h2>
Answer:</h2>
First we must find the opposite-reciprocal of the original slope.
current slope: 
new slope: 
Using the new slope and the given point, we will plug them into slope-intercept form and solve for b, the y-intercept.

The y-intercept is
.
Now, we can write the formula for the new line.
Slope-intercept form: 
Point-slope form: 