Someone explain to me how to solve and write out an equation in slope-intercept form for example: 4x-6y=12

Which ordered pair (c,d) is a solution to the given system of linear equations- c+2d=13 -9c-4d=-15

Rob spent 25%, percent more time on his research project than he had planned. he spent an extra h hours on the project. which of the following expressions could represent the number of hours rob actually spent on the project? two answers

Ineed with this problem 21 show steps