Question

The question says “the system below has been solved by graphing. How many solutions does it have?”

Answer 1

Infinitely many solutions

Explanation:

3x+y=1

15x+5y=5

Step: Solve3x+y=1 for y:

3x + y +−3 x = 1 + −3x (Add -3x to both sides)

y=−3x+1

Step: Substitute−3x+1 for y in 15x+5y=5:

15x+5y=5

15x+5(−3x+1)=5

5=5(Simplify both sides of the equation)

5+−5=5+−5(Add -5 to both sides)

0=0

so there are infinite solutions