Question

Solve by substitution x-2y= -25 and 3x-y=0

Answer 1

x=5 and y=15

Explanation:

x−2y=−25

x−2y+2y=−25+2y(Add 2y to both sides)

x=2y−25

Step: Substitute2y−25forxin3x−y=0:

3x−y=0

3(2y−25)−y=0

5y−75=0(Simplify both sides of the equation)

5y−75+75=0+75(Add 75 to both sides)

5y=75

5y

5

=

75

5

(Divide both sides by 5)

y=15

Step: Substitute 15fory in x=2y−25:

x=2y−25

x=(2)(15)−25

x=5(Simplify both sides of the equation)