# How do you solve the following system: # 8x-7y=-39, 7x − 5y = −11 #?

##### 2 Answers

#### Explanation:

(1)*5:

(2)*7:

(4)-(3):

Sub x=118/9 into (1)

I have solved

Check your solution with that in the graph.

#### Explanation:

I choose to answer this the traditional way.

Example of the principle used. When I realised this (long time ago) it opened the door for me to a whole new way of thinking.

Suppose we have

Then it is also true that

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Given:

If we change one or both of these then subtract it will eliminate one of the unknown. Then we have 1 equation with 1 unknown and thus solvable

Lets 'get rid' of the

Multiply

Divide both side by -9

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I will let you determine