In a quadratic function of the form ax^2+bx+c, which of the following is not true?

a) the y-intercept is c.
b) if a is positive, the parabola opens up.
c) the vertex has an x-coordinate of -b/2a.
d) the axis of symmetry is the line y=-b/2a.

Adrawer contains 12 identical white socks, 18 identical black socks and 14 identical brown socks. what is the least number of socks you must choose, without looking, to be certain that you have chosen two socks of the same colour?

During a bike challenge riders have to collect various colored ribbons each 1/2 mile they collect a red ribbon each eighth mile they collect a green ribbon and each quarter mile they collect a blue ribbion wich colors of ribion will be collected at the 3/4 markrer

Travis and paula went to lunch. travis ordered a sandwich for $7.50 and paula ordered a burger for $5.25.after lunch, they left a 15% tip for the waiter. how many money did they spend altogether?