
Michael D. answered 07/17/19
Versatile STEM tutor eager to teach
We get the following from the word problem. (The track is a rectangle with point A-B-C-D)
4*(AB+BC+CD+AD) = 1000
AB = CD = 25 + AD
BC = AD
plug in the 2nd & 3rd equations into the 1st equation
4*(AB+BC+CD+AD) = 1000
4*((25 + AD)+AD+(25 + AD)+AD) = 1000
4*(50+4*AD) = 1000
200+16*AD = 1000
16*AD = 800
AD = 50
BC = AD = 50
Now plug that into your 2nd equation to find AB & CD
AB = CD = 25 + AD
AB = CD = 25 + 50
AB = CD = 75
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Always check your work!
4*(AB+BC+CD+AD) = 1000
4*(75 + 50 + 75 + 50) 1000
4*250 = 1000
1000 = 1000 CORRECT!
AB = CD = 25 + AD
75 = 75 = 25 + 50
75 = 75 = 75 CORRECT!