You pay 5$ and 10$ to begin a membership. You need to spend at least 50$. Write an inequality.

An element with a mass of 990 grams decays by 16.9% per minute. To the nearest

melamori03 [73]

Answer:

It will take 13.58 minutes until there are 80 grams of the element remaining

Step-by-step explanation:

An element with a mass of 990 grams decays by 16.9% per minute.

We are supposed to find how long will it be until there are 80 grams of the element remaining

Formula : $N(t)=N_0(1-r)^t$

N(t)=Amount after t minutes

$N_0$ =Initial amount

r = rate of decrease = 0.169

t = time in minutes

Substitute the values in the formula :

$80=990(1-0.169)^t$

$\frac{80}{990}=0.831^t$

t=13.58

Hence It will take 13.58 minutes until there are 80 grams of the element remaining

5 0

3 years ago

Help!!! Determine how far it is across the lake

Naya [18.7K]

Tan(34) = a/700
a = 700*tan(34) =472.155 so 472

6 0

3 years ago

What are the first seven terms of the sequence whose first term is 100, and each term after the first is 8 less than the precedi

-BARSIC- [3]

100, 92, 84, 76, 68, 60, 52.

8 0

3 years ago

A triangular pyramid and its net are shown. Rain uses Calculations below to conclude that the surface area of a triangular pyram

Harman [31]

Answer:

Rain is correct, calculates correctly, 238.5 square inches

Step-by-step explanation:

The given triangular pyramid is shown with the dimensions.

The surface area of the triangular pyramid is given by :

$A=\frac{1}{2}\left(a \times b\right) + 3\left(\frac{1}{2}\times b\times s\right)$

$A=\frac{1}{2}\left(10 \times 8.7\right) + 3\left(\frac{1}{2}\times 10\times 13\right)$

$A=43.5+(3\times 65)$

$A=43.5+195$

$A=238.5 \ \text{inche}^2$

Therefore, the surface area of the triangular pyramid is = 238.5 square inches.

5 0

3 years ago

You need to solve a system of equations. You decide to use the elimination method. Which of these is not allowed? 2x - 3y = 12

suter [353]

Answer:

A.

Step-by-step explanation:

The Elimination Method is the method for solving a pair of linear equations which reduces one equation to one that has only a single variable.

If the coefficients of one variable are opposites, you add the equations to eliminate a variable, and then solve.

If the coefficients are not opposites, then we multiply one or both equations by a number to create opposite coefficients, and then add the equations to eliminate a variable and solve.

When multiplying the equation by a coefficient, we multiply both sides of the equation (multiplying both sides of the equation by some nonzero number does not change the solution).

So, option B is not allowed (it is not allowed to multiply only one part of the equation)

6 0

3 years ago