180 is the lcm for 20 and 18
The answer is 52
x - the number of students in a bus
4 + 9x = 472
9x = 472 - 4
9x = 468
x = 468 / 9
x = 52
Answer:
x = 0
, y = 7/6
Step-by-step explanation:
Solve the following system:
{18 y - 12 x = 21
6 x - 9 = -9
In the second equation, look to solve for x:
{18 y - 12 x = 21
6 x - 9 = -9
Add 9 to both sides:
{18 y - 12 x = 21
6 x = 0
Divide both sides by 6:
{18 y - 12 x = 21
x = 0
Substitute x = 0 into the first equation:
{18 y = 21
x = 0
In the first equation, look to solve for y:
{18 y = 21
x = 0
Divide both sides by 18:
{y = 7/6
x = 0
Collect results in alphabetical order:
Answer: {x = 0
, y = 7/6