Yeah it’s My favorite I’m really excellent in Math That’s My 1st favorite subject
Let us first write down the given equation.
80 = 3y + 2y + 4 + 1
80 = 5y + 5
80 - 5 = 5y
75 = 5y
Just reversing both sides we get
5y = 75
Now dividing both sides by 5 we get
y = 15
So the value of y is 15.
I hope the procedure for solving the problem is clear to
you. In future you can solve such problems with ease following the procedure
described.
Answer:
Option B. The equation has a maximum value with a y-coordinate of -21.
Step-by-step explanation:
The correct quadratic equation is

This is a vertical parabola open downward (the leading coefficient is negative)
The vertex represent a maximum
Convert to vertex form
Factor -3

Complete the square


Rewrite as perfect squares

The vertex is the point (2,-21)
therefore
The equation has a maximum value with a y-coordinate of -21
You would have to divide 105 by 7 and get an answer then you times that answer by nine and get your answer