Which value of C makes the ratios equal? 5/6=9/C

Ten times the square of a non-zero number is eqaul to ninety times the number

Will mark determine whether the conjecture is true or false. give a counterexample for any false conjecture. given: points r, s, and t conjecture: r, s, and t are coplanar. a) false; the points do not have to be in a straight line. b) true c) false; the points to not have to form right angles. d) false; one point may not be between the other two.

Can someone show me step by step how to do this?