First, you must understand the question. what % of 60 is 15, so I would write an equation to express this.
15 = 60x
From there, solve for x, so Divide by 60 on each side. The answer is 1/4, or 25%
3x^2 + 4x - 21x - 28
x(3x + 4) - 7(3x + 4)
(3x + 4) (x - 7)
Answer: B).
Well to find the value of x you need to get x alone. so you -1 from 3 and do 2/27 and your answer is 0.074