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Solve the system of equations using subsitutions. x-4y=111 and 2y-x=-7

User Kerris
by
5.3k points

2 Answers

3 votes

Answer:

(- 97, - 52)

Explanation:

given the 2 equations

x - 4y = 111 → (1)

2y - x = - 7 → (2)

Rearrange (1) expressing x in terms of y by adding 4y to both sides

x = 111 + 4y → (3)

Substitute x = 111 + 4y into (2)

2y - (111 + 4y ) = - 7 ← distribute and simplify left side

2y - 111 - 4y = - 7

- 2y - 111 = - 7 ( add 111 to both sides )

- 2y = 104 ( divide both sides by - 2 )

y = - 52

Substitute y = - 52 into (3) for corresponding value of x

x = 111 + 4(- 52) = 111 - 208 = -97

Solution is ( - 97, - 52 )

User Odesuk
by
5.0k points
4 votes

Answer:


(x)/(4)-(111)/(4)\\x=2y+7

I'm pretty sure this is correct!

User Mirtheil
by
5.8k points