Points C and D are equidistant from points A and B, so Dominic's square could be ACBD. To draw that square, his next move should be ...
... Use a straightedge to join points C and A, C and B, D and A, and D and B
Answer:
17/40
Step-by-step explanation:
4/5-3/8=32/40-15/40
=17/40
81x^4-1=(9x^2-1)(9x^2+1)
=(3x-1)(3x+1)(9x^2+1)