Solve the following ODEs by making an appropriate change of variable: dy 1-3y-9r (b) = dr 1+ y + 3x dy (a) (v² − z²¹) = - -2xy,

Find da. (2x-4) (2x+3)를 %3D

If 2x + 3ỹ = à and −x + 5ỹ = 6b, express x and y in terms of à and b.

If possible, write -1- 12x - 8x² as a linear combination of -x-x², 2x + x² and 2x1 + x². Otherwise, enter DNE in all answer blanks. (-x-x²)+ -1-12x8x² (2x − 1 + x²). = (2x + x²)+