Equation B is written in vertex form, which means you can read the vertex (extreme value) from the numbers in the equation.
Vertex form is
y = a(x -h)² + k
where the vertex (extreme point) is (h, k). Whether that is a maximum or a minimum depends on the sign of "a". When "a" is negative, the graph is a parabola that opens downward, so the vertex is a maximum.
Equation
B reveals its extreme value without needing to be altered.
The extreme value of this equation is a
maximum at the point
(2, 5).
Solve for the first variable in one of the equations, then substitute the result into the other equation.
3. (1/2, -1,2)
4. (2, -4)
You can get step by step at:
https://www.mathpapa.com/algebra-calculator.html
I think the answer would be C
NO.....9.66% less than $18,000 is $16,261.20
230×12= $2,760