Answer: In 4 minutes he will make 5 portraits
Step-by-step explanation:

Answer: It will cost him $237 to seed the entire backyard
Step-by-step explanation:
Hi, to answer this question, first, we have to calculate the area of the rectangular backyard:
Area of a rectangle = length x width
Replacing with the values given:
A = 20 x 15 = 300 ft2
Since seed cost 0.79 per square foot, we simply have to multiply that price by the area:
0.79 x 300 = $237
It will cost him $237 to seed the entire backyard
Feel free to ask for more if needed or if you did not understand something.
The parabola opens down, since the 'a' value of the equation is a negative value.