Answer:
9.6 square inches.
Step-by-step explanation:
We are given that ΔBAC is similar to ΔEDF, and that the area of ΔBAC is 15 inches. And we want to determine the area of ΔDEF.
First, find the scale factor <em>k</em> from ΔBAC to ΔDEF:

Solve for the scale factor <em>k: </em>
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Recall that to scale areas, we square the scale factor.
In other words, since the scale factor for sides from ΔBAC to ΔDEF is 4/5, the scale factor for its area will be (4/5)² or 16/25.
Hence, the area of ΔEDF is:

In conclusion, the area of ΔEDF is 9.6 square inches.
m_6 + m_8 = 180º because they form a straight line.
So, (2x-5) + (x+5) = 180
3x = 180
x = 60
So, m_115º (2•60 - 5 = 115)
Also, because the two lines are parallel m_6 = m_3 by alternate interior angles.
So, m_3 = 115º
Answer:
Volume = 315 cm³
Step-by-step explanation:
Volume = Length × Width × Height
→ Substitute in the values
Volume = 6 cm × 3.5 cm × 15 cm
→ Simplify
Volume = 315 cm³
Answer:
The test is not significant at 5% level of significance, hence we conclude that there's no variation among the discussion sections.
Step-by-step explanation:
Assumptions:
1. The sampling from the different discussion sections was independent and random.
2. The populations are normal with means and constant variance
There's no variation among the discussion sections
There's variation among the discussion sections

Df Sum Sq Mean sq F value Pr(>F)
Section 7 525.01 75 1.87 0.99986
Residuals 189 7584.11 40.13
Test Statistic = 

Since our p-value is greater than our level of significance (0.05), we do not reject the null hypothesis and conclude that there's no significant variation among the eight discussion sections.
Answer:
23 + 16 = 39
39 - 16 = 23
the student did not reverse the sum correctly