3x^4 becomes 3(3x)^4=3*3^4*x^4
y^2 becomes (3y)^2=3^2y²
the new z=3² the old z, so b is correct.
Answer:
5 seconds it will hit the water.
Step-by-step explanation:
y=-16t²+400
add -16t² to both sides
-16t²=-400
divide both sides by 16
t²=-25
t=√25
t=5
Answer:
They are only equal on day 0, both having 10 population.
Step-by-step explanation:
Given the bacteria on the counter is initially measured at 5 and doubles every 3 days we can generate the following geometric equation:

Given the bacteria on the stove is measured at 10 and doubles every 4 days we can create another equation:

To find how many days it will take for the bacteria population to equal the same lets set both equations equal to eachother:

Divide both sides by 10

Since both exponents have the same base we can set the exponents equal to eachother and solve for x:

Multiply both sides by 3 to isolate x on the left side

Multiply both sides by 4 to remove fraction

Subtract 3x to isolate x on the left side

Plug x into one of our original equations

Solve
