Respuesta :

Hi Mark

3x+y=4

2x+y=5

Solve 3x+y=4 for y

Add -3x to both sides

3x+y-3x=4-3x

y=-3x+4

Substitute -3x+4 for y in 2x+y=5

2x+y=5

2x-3x+4=5

Simplify both sides of the equation

-x+4=5

Add -4 to both sides

-x+4-4=5-4

-x=1

Divide both sides by -1

-x/-1= 1/-1

x=-1

Substitute -1 for x in y=-3x+4

y=-3x+4

y=(-3)(-1)+4

Simplify both sides of the equation

y=7

Answer: (-1,7)


I hope that's help ! Have a great weekend :)