Put -x^2+3=(2x-1)^2 into ax^2+bx+c=0

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?

When you have 25 numbers, and jake picks 3 random numbers and puts them back, what is the chance bob has of picking those 3 numbers when he picks 6 random numbers (without putting them back)? explain.

The candy store is having a 30% off sale. emma is going to buy $7.50 worth of candy.how much will she pay after the discount