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How do you solve the system of equations #y= x + 2# and #y = 5x + 5#?

Answer 1

Julia Adams

#(-3/4,5/4)#

Since both equations are expressed in terms of y we can equate the right sides.

#rArr5x+5=x+2larr" solve for x"#

subtract x from both sides.

#5x-x+5=cancel(x)cancel(-x)+2#

#rArr4x+5=2#

subtract 5 from both sides.

#4xcancel(+5)cancel(-5)=2-5#

#rArr4x=-3#

divide both sides by 4

#(cancel(4) x)/cancel(4)=(-3)/4#

#rArrx=-3/4#

Substitute this value into either of the 2 equations to obtain y

#"Using "y=x+2#

#x=-3/4toy=-3/4+2=5/4#

#"the solution is "(-3/4,5/4)# graph{(y-x-2)(y-5x-5)=0 [-10, 10, -5, 5]}

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