The two pieces are continuous for every 
So, our only concern is to make sure that the pieces "glue" continuously at x=7.
To ensure this, we evaluate both pieces at x=7, and impose that the two values are equal.
The first piece evaluates to

The second piece evaluates to

So, we want

We move all terms involving c to the left hand side, and all the numerical constants on the right hand side:

Answer:
-4
Step-by-step explanation:
-5+4= -1
-1-3= -4
-4-6= -10
-10+9= -1
-1-3= -4
Answer:
5
Step-by-step explanation:
The best design for this study is to do an independent and dependent experiment of the outcomes from different types of soils for tomato plants.