Answer:
x = 15
Step-by-step explanation:
=> x - 3 = 12
=> x = 15
We are told that 21% of the total cans is 63 cans, therefore
100% of all the cans collected would be.
(63*100)/21=300 cans were collected in all
Answer:

Step-by-step explanation:
Put x = 3, y = 2 and z = 5 to the given expression
:

Answer:
x = 12
Step-by-step explanation:
130 + y = 180 {linear pair}
y = 180 - 130
y = 50°
3x - 6 +8x + 4 + 50 = 180 {Angle sum property of triangle}
3x + 8x - 6 + 4 + 50 = 180 {Combine like terms}
11x + 48 = 180
11x = 180 - 48
11x = 132
x = 132/11
x = 12°