What is the value of y ?

Phillip had some bricks. he stacked them in 6 equal piles. which expression shows the number of bricks phillip put in each pile? let the variable m stand for the unknown number of bricks. m + 6 m÷6    m−6    6m

Find an equation of the line perpendicular to the graph of 28x-7y=9 that passes through the point at (4,1)

Prove sin2a + cos2a - 1 / sin2a + cos2a + 1 = 1 - tana / 1 + cota