What is the value of x in the equation - x - y = 30, when y = 15?

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

20 points 1. your friend, taylor, missed class today and needs some identifying solutions to systems. explain to taylor how to find the solution(s) of any system using its graph. 2. taylor graphs the system below on her graphing calculator and decides that f(x)=g(x) at x=0, x=1, and x=3. provide taylor some feedback that explains which part of her answer is incorrect and why it is incorrect. f(x)=2x+1 g(x)=2x^2+1

Can someone me with my math problems i have a bunch. i will give brainliest and lots of pleeeaaasssee