Can you please help me on 6(a-7)=-7(a-7)

If a(0,0,0) and b(2,2,2) are points in coordinate space, how many paths are there from a to b that move from one lattice point to another in the positive x-,y- or z- direction?

Atriangle with all sides of equal length is a/an triangle. a. right b. scalene c. equilateral d. isosceles

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.