How do you solve the system 3x-5y=7 and 2x+5y=13?
1 Answer
Point of intersection as at
Explanation:
Always look for the easiest way, if you can spot it that is! Sometimes you have no choice but to just jump in and do it the hard way. Not so in this case!
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Notice that both equations are in the same order
Notice that the coefficients of
To end up with only one variable and a pile of numeric values. This enables the determination of the variables value.
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Write as:
Add equation (1) to equation (2) to 'get rid of'
Divide both sides by 5 so that you end up with
But
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Substitute
Selecting equation (2) as
Subtract 8 from both sides
Divide both sides by 5
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Point of intersection as at