Solve the simultaneous equations

3x + 2y = 30
3x - y = 21

x = 8 , y = 3

Step-by-step explanation:

3x + 2y = 30

3x - y = 21      -> y = 3x - 21

3x + 2 (3x - 21) = 30

3x + 6x - 42 = 30

3x + 6x = 30 + 42

9x = 72

x = 72/9 = 8

y = 3*8 - 21 = 24 - 21 = 3

∴ x = 8 & y = 3

she played for 18.75 hours.

step-by-step explanation:

if she played 2/4 of a hour on tuesday. and there is 60 minutes in an hour and 60 divided by 4 is 7.5. and she played 2/4 of an hour on thursday then again 60 divided by 4 is 7.5, you add 7.5+7.5=56.25. now you have to do 1/4 of an hour, it equals 3.75. now you have to add them all up. 3.75+7.5+7.5=18.75

i hope this and i hope you get it right. it took me a while to get this done for you. : )

is there a picture

step-by-step explanation: