Your equation would be 2x - 12 + 3x - 15 = 23
Combine like terms and solve for x
The answer is 33. This is because there are 3 colours and the probability that the spinner will land on each colour is 1/3 (one third). To work out the number of times it will land on blue you have to do the probability of it landing on blue (1/3) multiplied by the number of times spun (100) which gives approximately 33.
3+(-5)x=19
Subtract 3 from both sides of the equation.
-5x= 16
Divide by -5 on both sides
X= -3.2