Question

What is the solution to the system of equations? Use the substitution method.
y-3x=7
21+9x=3y
A. There is no solution
B. There are an infinite number solutions
C. The solution is {1,10}
D. The solution is {28,0}

Answer 1

y -3x = 7  from this result y = 7 +3x what value of y we need substituting in place of y inside second equation and will get 
21 +9x = 3y 

21 +9x = 3(7 +3x)
21 +9x = 21 +9x
        0 = 0

so this mean that there are an infinite number solutions so choice B. is right 

Answer 2

Answer:

answer b

Step-by-step explanation: