We have been given that a huge ice glacier in the Himalayas initially covered an area of 45 square kilo-meters. The relationship between A, the area of the glacier in square kilo-meters, and t, the number of years the glacier has been melting, is modeled by the equation 
.
To find the time it will take for the area of the glacier to decrease to 15 square kilo-meters, we will equate 
and solve for t as:
Now we will switch sides:
Let us take natural log on both sides of equation.
Using natural log property 
, we will get:
Therefore, it will take 
years for area of the glacier to decrease to 15 square kilo-meters.
Answer:
I’m pretty sure it’s Triangle ABC is congruent to Triangle DEF.
Step-by-step explanation:
If you rotate Triangle DEF to where the 90 degree angle is on the bottom right, you can the compare the two triangles. You can divide 300/25, 240/20, and 180/15. They all result in 12 meaning they are congruent and similar in that way. (I’m only 90% this is right btw)
The first step of factoring is to try to factor out a common factor.
The terms x^2 and -9x have the factor x in common.
Factor out x from both terms.
x^2 - 9x = 0
x(x - 9) = 0
Now you have a product of fully factored terms equaling zero, so you can apply the zero product property to solve.
x = 0 or x - 9 = 0
x = 0 or x = 9
Answer: x = 0 or x = 9
8 Is your answer so option A
