How many square centimeters of material does Gretchen need to construct 3 bows for her sister's doll?

Don’t mind the writing.

Step-by-step explanation:

area of bow = area of 2 trapezium + area of rectangle

so, length of rectangle (l) = 6cm

breadth of rectangle (b) = 4cm

therefore, area of rectangle = l×b

                                              = 6×4 cm²

                                              = 24cm²

side a = 10cm

side b = 6cm

and , height of trapezium (h) = 5cm

therefore, area of trapezium = h(a + b) ÷ 2

                                               = 5 ( 6 + 10) ÷ 2

                                               = (5×16) ÷ 2

                                               = 80 ÷ 2

                                               = 40 cm²

area of trapezium = 40cm²

area of both trapeziums are equal as their sides and height are equal

so, area of 2 trapezium  = 2 × area of 1 trapezium  

                                        = 2 × 40

                                        = 80cm²

therefore, area of bow = area of 2 trapezium + area of rectangle

                                      =  80 + 24

                                      = 104cm²

area of 3 bow = 3 × area of 1 bow

                       = 3 × 104

                        = 312cm²

hence, gretchen need 312 square cm of material to construct 3 bows for her sister's doll

hello from mrbilldoesmath!

answer:

x - 3

discussion:

x^2 - 9 = (x-3) (x+3)   so

(x^2-9)/ (x + 3) = x-3

you,

mrb