Question

find the area of each triangle. round intermediate values to the nearest tenth. use the rounded values to calculate the next value. round your final answer to the nearest tenth.
11)
12)

Explanation:

Step1: Calculate height of triangle 11

First, split the base into two equal parts: $\frac{6.2}{2}=3.1$. Use Pythagorean theorem: $h=\sqrt{10^2 - 3.1^2}=\sqrt{100 - 9.61}=\sqrt{90.39}\approx9.5$

Step2: Find area of triangle 11

Use area formula: $\frac{1}{2}\times base\times height$
$\frac{1}{2}\times6.2\times9.5$

Step3: Calculate base of triangle 12

First find the unknown base segment: $\sqrt{6^2 - 4^2}=\sqrt{36 - 16}=\sqrt{20}\approx4.5$. Total base: $6 + 4.5=10.5$

Step4: Find area of triangle 12

Use area formula: $\frac{1}{2}\times base\times height$
$\frac{1}{2}\times10.5\times4$

Answer:

Triangle 11 area: $29.5$
Triangle 12 area: $21.0$