The function

is a parabola concave up, whose solutions are

from here, you can use the quadratic formula

to find that the solutions of the parabola are 
So, the parabola is positive if
(which wouldn't make sense in our case) or 
So, if Tanya caters 25 meals she breaks even, and starting with the 26th meal she will begin to profit.
Answer:

Step-by-step explanation:
Given

Required
Determine the roots
To get the root of the function, then f(b) must be 0;
i.e. f(b) = 0
So, the expression becomes

Add 75 to both sides


Take square roots of both sides


Reorder

Expand 75 as a product of 25 and 3

Split the expression




The options are not clear enough; however the roots of the equation are 
Answer:
Step-by-step explanation:
w^3 + 4w^2 + 5w - 12
Answer:
mini disc diameter:disc diameter
14cm:21cm = 7:10.5 = 3.5:5.25 = 1:1.5