Which choice is the most efficient first step to solve this set of equations? y=3x-5 and 2x+6y=20

Plug in 3x-5 to the second equation for every y value. (This is substitution)

2x + 6 (3x-5) = 20

2x+18x-30=20

20x=50

x=2.5

Then solve the first equation with your x value

y=3 (2.5) - 5

y=7.5-5

Y=2.5

To check plug the numbers into both

EQ 1: 2.5=7.5-5

EQ 2: 5+15=20

We substitute the value of y in equation (1) into (2)

Step-by-step explanation:

y=3x-5 ... (1)

2x+6y=20 ... (2)