A÷(a-b) - 2ab÷(a•a-b•b) can someone show me how to work this out (the first letter should be (a)

How do i do this? i don’t understand

John used linear combination to solve the system of equations shown. he did so by multiplying the first equation by -3 and the second equation by another number to eliminate the x-terms. what number did jonas multiply the second equation by? 4x-6y=23x+5y=11

Find the magnitude, correct to two decimal places, made by each of the following with positive direction of the x axis a) y= x the answer is 45° but i don’t know how