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1 vote
3х + y = 17
4х – у = 18

1 Answer

7 votes

Answer:

x=5 and y=2

Explanation:

Let's solve your system by substitution.

3x+y=17;4x−y=18

Step: Solve 3x+y=17 for y:

3x+y=17

3x+y+−3x=17+−3x(Add -3x to both sides)

y=−3x+17

Step: Substitute−3x+17 for y in 4x−y=18:

4x−y=18

4x−(−3x+17)=18

7x−17=18(Simplify both sides of the equation)

7x−17+17=18+17(Add 17 to both sides)

7x=35

7x

7

=

35

7

(Divide both sides by 7)

x=5

Step: Substitute 5 for x in y=−3x+17:

y=−3x+17

y=(−3)(5)+17

y=2(Simplify both sides of the equation)

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