How do i write 8.66 in radical form?

Combine the information in the problem and the chart using the average balance method to solve the problem.

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

What is the length of the segment, endpoints of which are intersections of parabolas y=x^2− 11/4 x− 7/4 and y=− 7 /8 x^2+x+ 31/8 ?