How to find the area under a curve?

Now Playing:Definite integral – Example 1a

Use the graph of $f$ to evaluate each integral by interpreting it in terms of areas.
1. $\int_{-1}^{1} f(x)dx$
2. $\int_{1}^{2} f(x)dx$
3. $\int_{2}^{4} f(x)dx$
4. $\int_{4}^{8} f(x)dx$
5. $\int_{8}^{9} f(x)dx$
6. $\int_{-1}^{9} f(x)dx$
Evaluate the integral by interpreting it in terms of areas.
1. $\int_{0}^{2}(2-2x)dx$
  
  0/4
2. $\int_{0}^{2}\sqrt{4-x^2}dx$
  
  0/1
3. $\int_{-2}^{1}|x|dx$
  
  0/6
if $\int_{3}^{10}f(x)dx=15$ and $\int_{3}^{8}f(x)dx=9$ , find $\int_{8}^{10}f(x)dx$

0/7