Asked and answered elsewhere.
brainly.com/question/9247314You obviously don't mind using "technology" (Brainly) to answer these questions. A graphing calculator can do quadratic regression on the sequence and tell you its formula.
If you want to do it by hand, you can write the equation
.. y = ax^2 +bx +c
and substitute three of the given points. Then solve the resulting three linear equations for a, b, and c.
.. 4 = a +b +c
.. 7 = 4a +2b +c
.. 12 = 9a +3b +c
Subtracting the first equation from the other two reduces this to
.. 3 = 3a +b
.. 8 = 8a +2b
The latter can be divided by 2, so reduces to
.. 4 = 4a +b
Subtracting the first of the reduced equations from this, you have
.. 1 = a
so
.. 3 = 3*1 +b
.. 0 = b
and
.. 4 = a + b + c = 1 + 0 + c
.. 3 = c
And your equation is
.. y = x^2 +3 . . . . . . as shown previously
Fit Fast: a set feet per class => y = Ax
Stepping Up: a monthly fee plus an additioal fee per class => h = Bx + C
You can discard the second and the fourth systems because they do not have the form established from the statement.
The first system produce an obvious result given that is represents an option that is always better than the other 5.5x will be lower than 7.5x + 10 for any positive value of x, and so there is no need to make any comparission.
The third system is
y = 7.5x and y = 5.5x + 10 which need to be solved to determine when one rate is more convenient than the other.
Answer: y = 7.5x and y = 5..5x + 10
Given
Answer
The graph touches the x-axis at -6
Hence x = -6 is the zero of the graph.