Find the value of x.
.
10
7

X = 12.21

Step-by-step explanation:

Since this is a right triangle, use the formula A^2 + B^2 = C^2 and plug in appropriate values.

(10)^2 + (7)^2 = C^2

100 + 49 = C^2

149 = C^2

12.2065 = C

Rounded to two decimal places, this makes X equal to 12.21.

step-by-step explanation: a reaction is first order. if the initial reactant concentration is 0.0200 m, and 25.0 days later the concentration is 6.25 x 10-4 m, then its half-life is: