Question

A system of equations is shown below.

2x-y=5
x+3y=0

Which statement is true regarding this system ?
A- to solve the system, multiply the second equation by 2 and then add the result to the first equations
B- to solve the system, multiply the first equation by 3 and then add the result to the second equation.
C- the system has no solution since the second equation is equal to 0.
D- the system has infinitely many solutions since the second equation is equal to 0

Answer 1

B- to solve the system, multiply the first equation by 3 and then add the result to the second equation.

I:2x-y=5
II:x+3y=0

I*3=6x-3y=15

I*3+II: 6x-3y+x+3y=15+0
7x=15
x=15/7

insert x=15/7 into II:
(15/7)+3y=0
3y=-15/7
y=-5/7