Answer:120 square cm
Step-by-step explanation:
40 x 3
Right 3 units is right out of the options given
Answer:a=-8
Step-by-step explanation:
4+7a=12+8a
So first you want to have the variables on the same side
4+7a-7a=12+8a-7a
This is how you got the 7a to the right side. Then you subtract 8a-7a So the equation becomes
4=12+a
Now there are two ways of doing this.
1. 4-12=12-12+a
You moved the 12 to the left side so you have the same variable on one side
4-12=-8
So then a=-8
Or
2. 4-4=12-4+a
0=8+a
then you would have to subtract 8 to keep 'a' by itself
-8=8-8+a
simplify it
-8=a
same thing
