Question

Solve the system of equations using substitution. y = 3x y = 6x + 3 (2, 15) (1, 3) (−1, −3) (−2, −6) answer

Answer 1

(-1, -3)

Explanation:

Pre-Solving

We are given the following system:

y = 3x

y = 6x + 3

We want to solve it via substitution. We can take the value of one of the variables, substitute that value as the variable in the other equation, then solve to get the value of the first variable.

Solving

Substitute 3x as y in y = 6x + 3.

3x = 6x + 3

Subtract 6x from both sides.

-3x = 3

Divide both sides by -3.

x = -1

Now, substitute -1 as x in either y = 3x or y = 6x + 3.

Taking y = 3x for instance:

Replace -1 for x in y = 3x.

y = 3(-1) = -3

So, the answer is x = -1 and y = -3. As a point, it is (-1, -3).