The following document is a report published in the Daily Democrat newspaper immediately after President Lincoln’s assassination. What kind of source is it?

Primary source

Explanation:

The primary sources provide first-hand evidence of an event, person and object. They are contemporary to the people and events. Whether something can be considered as a primary source or not depends on the context of the source which is being examined by you. To determine a primary source one can ask several questions such as who created the source, what is the source about and when was it created and the targeted audience of the source. Speech, newspaper articles, photographs, and govt documents are some of the primary sources.

simplify brackets

8 - 2a - 7 = a + 40

simplify 8 - 2a - 7 to -2a + 1

-2a + 1 = a + 40

add 2a to both sides

1 = a + 40 + 2a

simplify a + 40 + 2a to 3a + 40

1 = 3a + 40

subtract 40 from both sides

1 - 40 = 3a

simplify 1 - 40 o -39

-39 = 3a

divide both sides by 3

-39/3 = a

simplify 39/3 to 13

-13 = a

switch sides

a = -13