All you have to do is plug in the given values for a and b.
0.9a - 1.5b = ?
a = 15 b = 3
0.9 (15) - 1.5 (3)
= 13.5 - 4.5
= 9
Note:
•Integers are whole numbers. For ex: 1, 2, 3, 4...
•Decimals have a period in between 2 numbers For ex: 0.1, 0.2, 0.3
Sometimes when it’s concerning significant digits then decimals could also be 1.0, 2.0, 3.0 ... I wouldn’t worry about this right now until you get into higher years
