Which system has infinitely many solutions?

a. y=2x+6
y-8x=21

b. 4x-4y=4
x-y=1

c. 4x+2y=5
x-2y=9

d. none of these

Write as a product of 2 binomials and a monomial (factor out as much as possible from each binomial). ! i do not understand, any is appreciated : ) whoever gets the best answer recieves brainliest and points! (4x–12x²)(16y³+12y²)

Issof claims that the scale factor is 1/2. which statement about his claim is correct

Pls brainliest will be awarded if answer is correct