Find the values of the variables and please give the reasons​

180 ÷3 = 60 ° (angles on a straight line equals to 180 ° )

a+b+60 =180°

a+ b= 180 ° - 60° = 120°

(a+b) are 2 variables

so 120 ÷2 =60 °

therefore a and b =60 °

c +b+ 60° = 180° ( co - interior angles are supplementary angles )

c+60° +60° =180°

c +120° =180°

c =180°-120°

c=60 °

d=60° (alternate angles are equal )

or

c+b+d=180°

60° +60° + d = 180°

d=180°-120°

d=60°

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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