What is the vertex of the graph of y = x^2 + 4x?

Convert to vertex form  (  y = a(x - b)^2 + c where (b, c) is the vertex ):-

y = x^2 + 4x

y = (x + 2)^2 - 4

so the vertex is at ( -2, -4) answer

area of part 1:

a1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2

area of part 2:

a2=length*width=(8+2)*1=10 ft2

area of part 3:

a3=length*width=8*2=16 ft2

total shaded area : a1+a2+a3=41 ft2

total area of the reactangle : a=16*8=128 ft2

total area of the nonshaded region : 128-41=87 ft2

to find the total number of combinations, multiply the quantity of each item by each other:

2 pairs of shoes x 3 pairs of shorts = 6 different combinations.