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