How many solutions does the system of equations have?

x - 4y = 12 and 5x - 20y = 60

A) One
B) Two
C) Infinitely many
D) None

y - 7x = -14 and 7y - 49x = -2

A) One
B) Two
C) Infinitely many
D) None

Respuesta :

5x - 20y = 60...reduce by dividing by 5
x - 4y = 12
this is the same as the other equation....therefore, it is the same line...meaning infinite solutions
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y - 7x = -14
y = 7x - 14.....slope = 7, y int = -14

7y - 49x = -2
7y = 49x - 2
y = 7x - 2/7.....slope is 7, y int is -2/7

if the slopes are the same, but the y int are different, then u have a parallel lines with no solutions