n element with mass 570 grams decays by 18% per minute. How much of the element is remaining after 13 minutes, to the nearest 10th of a gram?

Step-by-step explanation:

Exponential Functions:

         y=ab^x

a=starting value=570

  r=rate=18%=0.18

Exponential Decay:

b = 1 - r = 1 - 0.18 = 0.82

Write Exponential Function:                             put it all together

y=570(0.82)^13

Plug in time for x:

y=570(0.82)^13

y=43.197134                                                       evaluate

ANSWER: y≈43.2                                              round

answer:   28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° =

but bc = 20 feet.

⇒ tan 55 ° =  

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348   ≈ 28.56 feet

center (1,3) with radius 6

step-by-step explanation:

we must complete the square to find the center and radius of the circle.

first make sure the x and y squared terms have 1 as their coefficients. we also make sure x and y terms together.

we now create space between the x and y terms with parenthesis.

we complete the square by taking the middle terms -2x and the -6y - divide each and square them.

we add the squares to both sides.

simplify.

and write the quadratics in factored form.

the center is (h,k) or (1,3). the radius is the square root of 36 which is 6.