solve using the multiplication principle -3a<-15

solve usins addition and multiplication 3c+4<-6
3c+4-4<-6+4
3c<-2
3c/3<2/3
c<-2/3 is this right

No.

Your error is in this line:

3c+4-4<-6+4

You should subtract 4 from both sides.

-6 and -4 = -10

To solve the inequality -3a < -15 using the multiplication principle, we want to isolate the variable "a" on one side of the inequality.

First, divide both sides of the inequality by -3, remembering to reverse the inequality sign because we are dividing by a negative number:

-3a / -3 > -15 / -3

This simplifies to:

a > 5

So, the solution to the inequality -3a < -15 is a > 5.

Now, let's move on to the second problem.

To solve the inequality 3c + 4 < -6 using addition and multiplication, we want to isolate the variable "c" on one side of the inequality.

First, subtract 4 from both sides of the inequality:

3c + 4 - 4 < -6 - 4

This simplifies to:

3c < -10

Next, divide both sides of the inequality by 3:

(3c) / 3 < (-10) / 3

This simplifies to:

c < -10/3

So, the solution to the inequality 3c + 4 < -6 is c < -10/3.

Therefore, c < -10/3 is the correct solution.