Ask question

Ask question

All categories

3 years ago

11

Sarah is playing a video game that allows her to double her coins each hour. The game starts with 4 coins and Sarah plays the ga

me for 2 hours. How many coins will she have at the end of the two hours.

1 answer:

Snezhnost [94]3 years ago

4 0

Answer:

16 coins

Step-by-step explanation:

At first: 4 coins

First hour: 4 x 2 = 8

Second hour: 8 x 2 = 16

Total coins: 16 coins

You might be interested in

a medical laboratory technician is staining blood film slides with wrights stain . the Wright strain bottle contains 90 milliter

Jet001 [13]

I don't know if I understand the question but I think it is 15

4 0

3 years ago

What is the surface area of this square pyramid

JulsSmile [24]

Answer:

Surface area of square pyramid shown in picture:

A = area of 4 triangles + area of square

= 4 x 4 x 3 x (1/2) + 3 x 3

= 33 (ft)

=> Option 4 (last one) is correct

Hope this helps!

:)

3 0

3 years ago

Identify the following as either an expression, an equation, or neither.<br>3x+(10 - x) = 3

n200080 [17]

The following is an expression.

6 0

3 years ago

Which of the following is a solution to 2cos2x − cos x − 1 = 0?

Pavel [41]

Answer:

Option A is correct.

Solution for the given equation is, $x = 0^{\circ}$

Step-by-step explanation:

Given that : $2\cos^2x -\cos x -1 =0$

Let $\cos x =y$

then our equation become;

$2y^2-y-1= 0$ .....[1]

A quadratic equation is of the form:

$ax^2+bx+c =0$ .....[2] where a, b and c are coefficient and the solution is given by;

$x = \frac{-b\pm \sqrt{b^2-4ac}}{2a}$

Comparing equation [1] and [2] we get;

a = 2 b = -1 and c =-1

then;

$y = \frac{-(-1)\pm \sqrt{(-1)^2-4(2)(-1)}}{2(2)}$

Simplify:

$y = \frac{ 1 \pm \sqrt{1+8}}{4}$

or

$y = \frac{ 1 \pm \sqrt{9}}{4}$

$y = \frac{ 1 \pm 3}{4}$

or

$y = \frac{1+3}{4}$ and $y = \frac{1 -3}{4}$

Simplify:

y = 1 and $y = -\frac{1}{2}$

Substitute y = cos x we have;

$\cos x = 1$

⇒ $x = 0^{\circ}$

and

$\cos x = -\frac{1}{2}$

⇒ $x = 120^{\circ} \text{and} x = 240^{\circ}$

The solution set: $\{0^{\circ}, 120^{\circ} , 240^{\circ}\}$

Therefore, the solution for the given equation $2\cos^2x -\cos x -1 =0$ is, $0^{\circ}$

8 0

3 years ago

Read 2 more answers

Larry makes sandwiches for lunch everyday. he can make 5 sandwiches with every 3 tomatoes he buys. if he bought 9 tomatoes, how

tangare [24]

15 sandwiches
3 tomatoes= 5 sandwiches.
So if there's 9, that makes 3 groups of 3 tomatoes which would make 3x5 or 5+5+5 ;-;
15.

6 0

3 years ago