Answer:
t= <u>r-21</u>
7
Step-by-step explanation:
r = 7(t+3)
expanding the bracket
r = 7t + 21
bringing t to the left hand side
7t = r - 21
divide both sides by seven
t= <u>r-21</u>
7
You work it backwards.
-- If there were 4 children and each child got 4 pieces,
then the children got (4 x 4) = 16 pieces altogether.
-- That's what was left after he took 2 pieces for himself.
So he started with (16 + 2) = <em>18 pieces</em>.
Check the picture below.
Make sure your calculator is in Degree mode.