Fill in the blanks of the following: `x/7=y/3=(3x+5y)/………=(7x-9y)/…….`

Fill in the blanks: x/7=y/3=(7x-9y)/(square)

Fill in the blanks: x/3=y/5=z/4=(5x+3y+4z)/(square)

Examine the consistency of the following equations: x-2y=3,3x+4y=-1,2x+7y=-5

Find (d^2 y)/(dx^2) of the following: y= x^3 + 5 x^2 -7 x + 10

Fill in the blanks : (2x+5y)(2x+5y)=(2x)^2+(......)xx2x+(5y)^2

Select and write the correct answer from the given alternatives in each of the following:If the equations 2x+5y=9,7x-ky=4,3x+y=8 are consistent,then k is