Doctors use the term  maximum heart rate  (mhr) when referring to the quantity found by starting with 220 beats per minute and subtracting 1 beat per minute for each year of a person's age. doctors recommend exercising 3 or 4 times each week for at least 20 minutes with your heart rate increased from its resting heart rate (rhr) to its training heart rate (thr), where

thr  =  rhr  + .65(mhr  -  rhr)

which of the following is closest to the  thr  of a 43-year-old person whose  rhr  is 54 beats per minute?

step-by-step explanation:

always plug in x. in this case, x equals 4.

i'm going to first solve 4(2+3x)

1) 4(2+3(4)) use pemdas to solve.

i'm going to multiply whats in the parenthesis first, so 3 times 4=12.

2)4 (2+12) i'm then going to multiply 4 by both numbers in the parenthesis (because multiplying comes before adding)

4 times 2= 8.   4 times 12= 48

4) (8+48)= 56 (answer)

i'm then going to solve 8+12x and plug in 4 for x.

1) 8 +12(4)

multiplying comes before adding, so i'm gonna multiply 12 and 4.

12 times 4= 48.

2) 8+48=56

both equal the same!

i those same problems in math and dont know how to do them

i believe the answer is y=0.25x+-3