19. -x-2 = 2/3x + 3
5/3 x + 3 = -2
5/3x = -5
x = -3
20. none are correct, you can double check me by plugging in the x and y values in the coordanates into the first problem none of them worked out in the first equasion so no need to test the second
21. -3 is the answer, capable of being done by using desmos
Okay what’s the question ?
He has done 70 push ups because by the 15th he has done 35 push ups add 15 more days and u get 70 .
|DF| = |DE| + |EF|
|DF| = 9x -36
|DE| = 47
|EF| = 3x+10
Substitute:
9x - 39 = 47 + 3x + 10
9x - 39 = 3x + 57 |+39
9x = 3x + 96 |-3x
6x = 96 |:6
x = 16
Put the value of x to the equation |EF| = 3x + 10
|EF| = (3)(16) + 10 = 48 + 10 = 58
Answer: |EF| = 58
