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 b

Explanation: