PLEASE HELP ME WITH THIS

Jake bakes and sell apple pies. he sells each pie for $5.75 . the materials to make the pies cost $40. the boxes jake puts the pies in cost & 12.50 total. how many pies does jake need to sell to earn a profit of $50

When is g(x) = 0 for the function g(x) = 5.23x + 4?

What adds to be the bottom number but also multiplies to be the top number with 8 on the bottom and 15 on top