Question

Solve the system by substitution.
y = 5x
y = 9x + 4

Answer 1

(-1, -5)

Explanation:

`\left \{ {{y=5x} \atop {y=9x+4}} \right.`

1. We must calculate x, for that we must substitute y, so we have:

5x=9x+4

2. Now we solve the equation.

5x-9x=4

-4x=4

x=-1

3. Now we must calculate y

y=5x

y=5(-1)

y=-5

And the answer is (-1, -5)