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How do you solve the following system: #-2x + 5y = 20, 2x +5y = 5 #?

Answer 1

#-2x+5y=20-----(1)# #2x+5y=5------(2)# By adding eqn (1) and eqn(2) we get #-cancel2x+5y+cancel2x+5y=20+5# #=>10y=25# #=>y=25/10=5/2# putting the value of y in eqn(2) #2x+5*5/2=5# #=>2x=5-25/2=-15/2# #=>x =- 15/4=-3 3/4#

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Answer 2

Hazel Anglin

To solve the system of equations -2x + 5y = 20 and 2x + 5y = 5, you can use the method of elimination. Add the two equations together to eliminate the variable x. Then, solve for y. Once you have the value of y, substitute it back into one of the original equations to solve for x.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.