Answer: the y-coordinate that completes the point is 5.
Explanation:
An ordered pair (x, y) indicates the x-and-y coordinates of a general point, where x is the input value of a function and y is the output value.
The output value is y = f(x) and must be found applying the rule (function) to the given input value.
In this case the rulte is f(x) = - 3x + 2, and the input value, x, is - 1 (the first value of the ordered pair).
This is the mathematical procedure:
- x = - 1
- f(x) = f (-1) = -3 (-1) + 2 = 3 + 2 = 5.
Y = -x + 4.....so sub in -x + 4 in for y in the other equation
x + 2y = -8
x + 2(-x + 4) = -8
x - 2x + 8 = -8
x - 2x = -8 - 8
-x = -16
x = 16
y = -x + 4
y = -16 + 4
y = - 12
one solution (16,-12)
These are the steps. Just follow the numbers on the left hand side. Hopes this helps. The answer is -3.