Appendix A - Review - A.2 Geometry Essentials - A.2 Assess Your Understanding - Page A19: 29

$4$ square inches

The area $A$ of a triangle is given by the formula $A=\frac{1}{2}bh$ where $b$ is the base and $h$ is the height. Substitute the given values into the formula to obtain: $A=\frac{1}{2}bh$. $A=\frac{1}{2}(2\text{ in.})(4\text{ in.})$ $A=4\text{ in.}^2$ Hence, the area of the triangle is $4$ square inches.