Answer:
Step-by-step explanation:
A. (b - 10)(b + 10) = 180
[tex]b^{2}[/tex]-100 = 180
[tex]b^{2}[/tex]= 280
b = [tex]\sqrt{280}[/tex]
b = 2[tex]\sqrt{70}[/tex]
Your A is correct.
B. 2[tex]\sqrt{70}[/tex] - 10 = c
c = 6.733200531 = 6.73 Try rounding to 3 significant figures.
C. 2[tex]\sqrt{70}[/tex] + 10 = d
d = 26.73320053 = 26.7
You are correct in all 3 answers. Perhaps you should try rounding to 3 significant figures for your c and d values.
I hope this helps!! ^-^
