1)Which of these systems of linear equations has an infinite number of solutions?
A)3x-8y=21
6x-16y=46
B)3x+6y=22
6x+12y=44
C)5x+7y=24
10x-14y=48
D)5x-9y=20
10x+18y=40

2)Consider the system of linear equations?
5x+10y=15
10x+3y=13
to use the linear combination method and addition to eliminate the x-terms, by which number should the first equation be multiplied
A)-2
B)-1/2
C)1/2
D)2
PLEASE HELPPPP