Answer:
for the last question, there is a slope calculator on the internet that could help with that
Area of the field should be 9*10 = 90 square feet.
a bag of grass seeds cover 15 square feet.
so if you need to know how many bags should be used, then,
Total area of field/ area covered by 1 bag of grass seeds.
= 90/15 = 6 bags
he needs to use 6 bags of grass seeds to cover the whole field.
I don't think there are any 'hidden' questions, though you can consider the 2nd part of the question I guess. (how many bags of seed will Paul...)
42%
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It has a minimum value at x = 3 and f(x) = 4
Vertex form is
f(x) = a(x - 3)^2 + 4 where a is some constant to be found
From the graph when x = 5 f(x) = 15, so
15 = a * 2^2 + 4
a = 15-4/4 = 11/4
so our equation is f(x) = 11/4(x - 3)^2 + 4