Alisa is making a design for the bottom of a dress using trapezoid shapes cut from different colors of fabric. Each trapezoid has base lengths 5 inches and 10 inches and a height of 6 inches. How much fabric does she need for 4 trapezoids?

Well we are going to use the formula of a trapezoid.

What'd given is that two bases are 5 and 10 and the height is 6

add the two bases: 10 + 5 = 15 multiply it by 6 = 15 x 6 = 90 then divide by 2 = 45 since she is making 4 multiply it by 4,

45 x 4 = 180 fabric she needs.

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

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