Answer:
-60
Step-by-step explanation:
Factor the problem out using FOIL.
The end result is: −60
−84x+9
The value of coefficent a (the number in front of the x^2) is -60.
Answer: -8-10
Step-by-step explanation:
Vertex: (2,1)
axis of symmetry: (0,2)
direction of opening: up
not sure what optimal value is.
y-intercept: (0,5)
not sure what the step pattern is.
So we just need to plug in our values and solve

we are given v is 369 so we have

now we solve for x.
divide both sides by 20
square both sides
subtract 273 from both sides

so a temp of about 67 degrees C