The scale from the actual coin to the photo is 8 mm to 2 cm. In the photo, the distance across the coin is 3.25 cm. What is the distance across the actual coin?

13 mm

Step-by-step explanation:

Given that scale from actual coin to the photo is

8 mm to 2 cm.

Distance across the coin in photo  is 3.25 cm.

To find:

Distance across the actual coin = ?

Solution:

First of all, let us learn about scaling concept.

The concept of scaling is used to represent the actual object as as image so that it can be drawn on a paper.

This scaling can result in a smaller image or a bigger image depending upon the size of object.

Here, 8 mm coin is represented as 2 cm coin on the photo.

Let us use unitary method to identify the distance across actual coin to the distance across photo.

2 cm ---- 8 mm

1 cm ------

3.25 cm ------- 4 \times 3.25 mm = 13 mm

d, x=8

step-by-step explanation:

simplifying

4x + -5 = 2x + 11

reorder the terms:

-5 + 4x = 2x + 11

reorder the terms:

-5 + 4x = 11 + 2x

solving

-5 + 4x = 11 + 2x

solving for variable 'x'.

move all terms containing x to the left, all other terms to the right.

add '-2x' to each side of the equation.

-5 + 4x + -2x = 11 + 2x + -2x

combine like terms: 4x + -2x = 2x

-5 + 2x = 11 + 2x + -2x

combine like terms: 2x + -2x = 0

-5 + 2x = 11 + 0

-5 + 2x = 11

add '5' to each side of the equation.

-5 + 5 + 2x = 11 + 5

combine like terms: -5 + 5 = 0

0 + 2x = 11 + 5

2x = 11 + 5

combine like terms: 11 + 5 = 16

2x = 16

divide each side by '2'.