Ask question

Ask question

All categories

3 years ago

8

This is a picture of a cube and the net for the cube. What is the surface area of the cube?

1 answer:

mina [271]3 years ago

4 0

Answer:

$486\ in^2$

Step-by-step explanation:

we know that

The surface area of the cube is equal to the area of its six square faces

so

$SA=6b^2$

where

b is the length side of the cube

we have

$b=9\ in$

substitute

$SA=6(9)^2=486\ in^2$

You might be interested in

A person on tour has dollar 360 for his daily expenses. If he extends his tour for 4 days, he has to cut down his daily expenses

mash [69]

Answer:

The original duration of the tour = 20 days

Step-by-step explanation:

Solution:

Total expenses for the tour = $360

Let the original tour duration be for $x$ days.

So, for $x$ days the total expense = $360

<em>Thus the daily expense in dollars can be given by</em> = $\frac{360}{x}$

Tour extension and effect on daily expenses.

The tour is extended by 4 days.

<em>Tour duration now</em> = $(x+4)$ days

On extension, his daily expense is cut by $3

<em>New daily expense in dollars </em>= $(\frac{360}{x}-3)$

Total expense in dollars can now be given as: $(x+4)(\frac{360}{x}-3)$

Simplifying by using distribution (FOIL).

$(x.\frac{360}{x})+(x(-3)+(4.\frac{360}{x})+(4(-3))$

$360-3x+\frac{1440}{x}-12$

$348-3x+\frac{1440}{x}$

We know total expense remains the same which is = $360.

So, we have the equation as:

$348-3x+\frac{1440}{x}=360$

Multiplying each term with $x$ to remove fractions.

$348x-3x^2+1440=360x$

Subtracting $348x$ both sides

$348x-348x-3x^2+1440=360x-348x$

$-3x^2+1440=12x$

Dividing each term with -3.

$\frac{-3x^2}{-3}+\frac{1440}{-3}=\frac{12x}{-3}$

$x^2-480=-4x$

Adding $4x$ both sides.

$x^2+4x-480=-4x+4x$

$x^2+4x-480=0$

Solving using quadratic formula.

For a quadratic equation: $ax^2+bx+c=0$

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

Plugging in values from the equation we got.

$x=\frac{-4\pm\sqrt{(4)^2-4(1)(-480)}}{2(1)}$

$x=\frac{-4\pm\sqrt{16+1920}}{2}$

$x=\frac{-4\pm\sqrt{1936}}{2}$

$x=\frac{-4\pm44}{2}$

So, we have

$x=\frac{-4+44}{2}$ and $x=\frac{-4-44}{2}$

$x=\frac{40}{2}$ and $x=\frac{-48}{2}$

∴ $x=20$ and $x=-24$

Since number of days cannot be negative, so we take $x=20$ as the solution for the equation.

Thus, the original duration of the tour = 20 days

6 0

3 years ago

Help needed ASAP will give brainliest AND 5 STARS

blsea [12.9K]

Answer:

6

Step-by-step explanation:

6 0

3 years ago

The sixth grade is raising money for a camping trip that costs $2,500. So far they have raised 70% of the cost. How much have th

ratelena [41]

Answer:

Step-by-step explanation:

They have raised $1,750 so far. 70% of $2,500 is $1,750

7 0

3 years ago

Read 2 more answers

Are these lines parallel explain?

nata0808 [166]

Answer: Yes

Step-by-step explanation: hope it helps

6 0

2 years ago

Read 2 more answers

What’s the answerrrrr?

steposvetlana [31]

The answer is 95.

First: find the area if the whole rectangle. To do so you would multiply lxw (10x12)

Second: you would find the area of the square. Squares have perfect sides so you would multiply 5x5.

Last: take the sums of both equations. So the it would be 120-25=95.

7 0

3 years ago