How do I solve this? Trying to help my son but he didn’t take any notes! Help please!

Use continuity to evaluate the limit. lim x→16 20 + x 20 + x step 1 consider the intervals for which the numerator and the denominator are continuous. the numerator 20 + x is continuous on the interval the denominator 20 + x is continuous and nonzero on the interval

The parabola x = y² - 9 opens: a.)up b.)down c.) right d.)left

What is the value of x in the equation 2(x-4) = 4(2x + 1)?