All categories

3 years ago

Use Julia’s work and finish finding the areas of the faces what is the surface area of the rectangular pyramid

Mathematics

1 answer:

hoa [83]3 years ago

6 0

Answer:

The surface area of the rectangular pyramid is $SA=109.50\ m^{2}$

Step-by-step explanation:

we know that

The surface area of the rectangular prism is equal to the area of the rectangular base plus the area of the four triangular faces

$SA=(8)(5)+2[14.75]+2[\frac{1}{2}(8)(5)]$

$SA=40+29.50+40$

$SA=109.50\ m^{2}$

You might be interested in

Use the graph to estimate the value of y when x = 2.5

Vera_Pavlovna [14]

Answer:

Step-by-step explanation:

3 0

3 years ago

Amanda and jamie are standing 25 feet apart and spot a bird in the sky between them the angle of elevation from Amanda is 25 fee

finlep [7]

Answer:

25.2294 feet

Step-by-step explanation:

We can solve this question drawing a triangle using the values given and then using the law of sines. (See image attached to know how to draw the triangle and use the values).

First we need to find the third angle of the triangle, that is, the angle in the vertix where the bird is:

y + 55 + 63 = 180

y = 62°

The relation between the angles and the distances are:

25 / sin(y) = x / sin(63)

25 / 0.8829 = x / 0.8910

x = 25 * 0.8910 / 0.8829 = 25.2294 feet

4 0

3 years ago

What is the perimeter of a square with side length (2x-3)?

Elis [28]

Answer:

Perimeter = 8x - 12

Step-by-step explanation:

The perimeter of a square is:

p = 4(side length)

on this case:

p = 4(2x-3)

p = 4*2x + 4*-3

p = 8x - 12

7 0

3 years ago

A piece of cardboard has the dimensions (x + 15) inches by (x) inches with the area of 60 in 2 . Write the quadratic equation th

pochemuha

Answer:

$x^2 + 15x - 60 = 0$

The actual dimension is 18.28 by 3.28

Step-by-step explanation:

Given

Dimension:

$(x + 15)\ by\ x$

$Area = 60in^2$

Required

Determine the quadratic equation and get the possible values of x

Solving (a): Quadratic Equation.

The cardboard is rectangular in shape.

Hence, Area is calculated as thus:

$Area = Length * Width$

$60= (x + 15) * x$

Open Bracket

$60= x^2 + 15x$

Subtract 60 from both sides

$x^2 + 15x - 60 = 0$

<em>Hence, the above represents the quadratic equation</em>

Solving (b): The actual dimension

First, we need to solve for x

This can be solved using quadratic formula:

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

Where

$a = 1$

$b = 15$

$c = -60$

So:

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

$x = \frac{-15 \± \sqrt{15^2 - 4*1*-60}}{2*1}$

$x = \frac{-15 \± \sqrt{225 + 240}}{2}$

$x = \frac{-15 \± \sqrt{465}}{2}$

$x = \frac{-15 \± \21.56}{2}$

Split:

$x = \frac{-15 + 21.56}{2}$ or $x = \frac{-15 - 21.56}{2}$

$x = \frac{6.56}{2}$ or $x = \frac{-36.36}{2}$

$x = 3.28$ or $x = -18.18$

But length can't be negative;

So:

$x = 3.28$

The actual dimensions: $(x + 15)\ by\ x$ is

$Length =3.28 +15$

$Length =18.28$

$Width = x$

$Width =3.28$

<em>The actual dimension is 18.28 by 3.28</em>

3 0

3 years ago

A metalworker has a metal alloy that is 25% copper and another alloy that is 70% copper. How many kilograms of each alloy shou

Norma-Jean [14]

Answer:

Step-by-step explanation:

let 25 % copper=x kg

75 % copper=(100-x) kg

0.25 x+(100-x)*0.75=100*0.61

25x+7500-75 x=6100

-50 x=-1400

50 x=1400

5x=140

x=28

25 % of Copper=28 kg

75 % of Copper=100-28=72 kg

8 0

3 years ago

Read 2 more answers