For this case we have that by definition, the area of a square is given by:
![A = l ^ 2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/wwa1vdcatq4jkw1yvv6xt32rhh4hlk5stj.png)
In this case, the square is 9 \ in side, then:
![A = 9 ^ 2\\A = 81 \ in ^ 2](https://img.qammunity.org/2020/formulas/mathematics/high-school/ftlx2tqftysj0neu8s0qtf2bsojjyrq9ei.png)
On the other hand, the area of a triangle is given by:
![A = \frac {1} {2} b * h](https://img.qammunity.org/2020/formulas/mathematics/high-school/a6kzv7mf47580r4i4wlhfgwdjdjpt2ksoy.png)
Where:
b: It is the base of the triangle
h: It is the height
We have according to the figure that:
![b = 9-5 = 4 \ in\\h = 9-4 = 5 \ in](https://img.qammunity.org/2020/formulas/mathematics/high-school/d9azidexij16019ek2xcs0s6u57u5c9vs5.png)
So:
![A = \frac {1} {2} (4 * 5)\\A = \frac {20} {2}\\A = 10 \ in ^ 2](https://img.qammunity.org/2020/formulas/mathematics/high-school/ycw73yu0e1tr7w34afrg1t6xzef1pgz4il.png)
Finally, the area of the figure is:
![A_ {t} = 81 \ in ^ 2-10 \ in ^ 2\\A_ {t} = 71 \ in ^ 2](https://img.qammunity.org/2020/formulas/mathematics/high-school/cfde3sdqtjbj21v42kj5794a1f5s6p992p.png)
Answer:
![A_ {t} = 71 \ in ^ 2](https://img.qammunity.org/2020/formulas/mathematics/high-school/o2kssokr27y3zww8nae44l6phria1ey4q1.png)