There are 49 gallons of red paint.
I figured it out by doing the following:

If you subtract the gallons of pink paint (21) from the total number of gallons (70), then you get the number of gallons of red paint (49) because 49 + 21 = 70. I hope that helps :)
Answer:
Given, 3x−2<2x+1
⇒3x−2x<1+2
⇒x<3orx∈(−∞,3)
The lines y=3x−2 and y=2x+1 both will intersect at x=3
Clearly, the dark line shows the solution of 3x−2<2x+1.
Step-by-step explanation:
For this case we have the following system of equations:

We multiply the first equation by -5:

Thus, we have the equivalent system:

We add the equations:

We find the value of the variable "x":

Thus, the solution of the system is:

Answer:
