Can you help please Expand each expression and combine like terms if possible
2/3 (x+ 18 - 2x)

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.  

If x-1 and x+3 are the factors of x3+10x2+ax+b find a and b