Ask question

Ask question

All categories

2 years ago

5

An electrician charges $40 to come to your house.She also charges $55for each that she works. The electrician charges you total

of$190.How many hours does the electrician work at your house?

1 answer:

shusha [124]2 years ago

5 0

Answer:

Step-by-step explanation:

First, write an equation. 55x+40=190.

X represents the hours the electrician works. The 55 represents the $55 that she charges for each hour she works. The +40 for the $40 that was the price just to come to your house. The 190 is the total cost. Now, solve that equation.

55x+40=190

55x=150

x=2.72727272...

So the answer is 2.727 hours. It can be rounded as needed or turned into a decimal, 2 8/11.

You might be interested in

6 red marbles out of 36 marbles

Andreyy89

Answer:

1/6

Step-by-step explanation:

P(red) = red/total

=6/36

=1/6

6 0

3 years ago

use the elimination method to solve the system of equations. choose the correct ordered pair x+y=3 y=8

klasskru [66]

Answer:

(-5, 8)

Step-by-step explanation:

Step 1: Multiply 2nd equation by -1

x + y = 3

-y = -8

Step 2: Elimination

x = -5

Step 3: Find <em>y</em>

y = 8

7 0

2 years ago

A closed, rectangular-faced box with a square base is to be constructed using only 36 m2 of material. What should the height h a

kkurt [141]

Answer:

$b=h=\sqrt{6}$ m

Step-by-step explanation:

Let

Bas length of box=b

Height of box=h

Material used in constructing of box=36 square m

We have to find the height h and base length b of the box to maximize the volume of box.

Surface area of box= $2b^2+4bh$

$2b^2+4bh=36$

$b^2+2bh=18$

$2bh=18-b^2$

$h=\frac{18-b^2}{2b}$

Volume of box, V= $b^2h$

Substitute the values

$V=b^2\times \frac{18-b^2}{2b}$

$V=\frac{1}{2}(18b-b^3)$

Differentiate w. r.t b

$\frac{dV}{db}=\frac{1}{2}(18-3b^2)$

$\frac{dV}{db}=0$

$\frac{1}{2}(18-3b^2)=0$

$\implies 18-3b^2=0$

$\implies 3b^2=18$

$b^2=6$

$b=\pm \sqrt{6}$

$b=\sqrt{6}$

The negative value of b is not possible because length cannot be negative.

Again differentiate w.r.t b

$\frac{d^2V}{db^2}=-3b$

At $b=\sqrt{6}$

$\frac{d^2V}{db^2}=-3\sqrt{6}$

Hence, the volume of box is maximum at $b=\sqrt{6}$ .

$h=\frac{18-(\sqrt{6})^2}{2\sqrt{6}}$

$h=\frac{18-6}{2\sqrt{6}}$

$h=\frac{12}{2\sqrt{6}}$

$h=\sqrt{6}$

$b=h=\sqrt{6}$ m

7 0

3 years ago

Does the point (–3, 2) lie inside, outside, or on a circle with center (4, 0) and radius 5 units?

anastassius [24]

Answer:

The point (-3, 2) lies outside of the circle centered at (4, 0) with radius 5.

Step-by-step explanation:

The distance between two points (x₁, y₁) and (x₂, y₂) on the x-y plane can be calculated with:

√((x₁ - x₂)² + (y₁ - y₂)²)

So in this case, with the points (-3, 2) and (4, 0), the distance is:

√((-3 - 4)² + (2 - 0)²)

√(49 + 4)

√(53) ≈ 7.28

Since 7.28 > 5, the point (-3, 2) lies outside of the circle centered at (4, 0) with radius 5.

8 0

3 years ago

Find the lcm 15 and 20

Anestetic [448]

Answer:

5

Step-by-step explanation:

5 0

2 years ago

Read 2 more answers