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Solve using algebreic methods y=x^2+5x, y=7-x

1 Answer

5 votes

Answer:

x = 1 and x = -7

Explanation:

Given that,


y=x^2+5x ...(1)

and

y = 7 -x ....(2)

Put the value of y from equation (2) in (1)


7-x=x^2+5x\\\\x^2+5x-7+x=0\\\\x^2+6x-7=0\\\\x^2+7x-x-7=0\\\\x(x+7)-1(x+7)=0\\\\(x-1)(x+7)=0

So,

x = 1 and x = -7

Hence, the solution of the given equations is x = 1 and x = -7

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