The first friend your very welcome
Normally you would only solve by completing the square if a is 1 and b is even. But the answer would be half of b. So half of 9 is 4.5 or 4(1/2).
Find 3/4 of 16.
16 * 3/4
48/4
12
<span>So she uses 12 gallons of gas.</span>
The second answer i think is the best one
Area of each side triangle is 1/2*8*15 = 60. There are 5 of them so the triangles have surface area 300. the pentagon's area 1/2*apothegm*sidelength*sides = 1/2*5.5*8*5 = 110. The total area is therefore 300+110 = 410