How would these two problems be solved? i'm very rusty.

D, J

Step-by-step explanation:

21)

recall for a linear equation in the form

y=mx + b, where m is the slope

the slope a a line that is perpendicular to the equation is given by m' = -1/m

in this case the line is given with the slope of 3/4

hence the slope of a perpendicular line must be,

-1 / (3/4) = -4/3  (Hence D is the answer)

22)

M is the midpoint between Q (a,d) and R (c,b). Using the midpoint formula (see attached), we find the coordinates of M to be:

M [ (a+c)/2 , (d+b)/2 ]

The distance between P(a,b) and M [ (a+c)/2 , (d+b)/2 ] is given by (see other attached formula):

√ [(a+c)/2 - a]² + [(d+b)/2 - b]²

= √ [(a+c)/2 - (2a/2)]² + [(d+b)/2 - (2b/2)]²

= √ [(a+c - 2a)/2]² + [(d+b-2b)/2]²

= √ [(c - a)/2]² + [(d-b)/2]² (J is the answer)

assuming you mean addition: addition and subtraction are reverse operations.

step-by-step explanation:

c

step-by-step explanation: