The question is asking you to find the value of the expression for when c = 100, so we have to put 100 where c is in the equation. Given that fact, we start with c/5, then put the 100 in for c. c/5 = ?? 100/5 = 20. </span>
The y intercept is always c (-5) and to the axis of symmetry u do -b/2a which is -1 and the vertex is (-1,10) because u pug in -1 into the equation. lmk if it’s right!