Please help me!, 40 points!

Mathematics

2 answers:

Phoenix [80]3 years ago

7 0

Answer:

What is the question?

Step-by-step explanation:

Alexandra [31]3 years ago

4 0

Answer:

what is the question

Step-by-step explanation:

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Find the total surface area of this prism.

vovangra [49]

2.5 x 10 = 25 m^2
1.5 x 10 = 15 m^2
2 x 10 = 20 m^2
0.5 x 1.5 x 2 = 1.5 m^2 (2 times)
Total = 63 m^2
So just fill in 63.

7 0

3 years ago

The vertices of a triangle ABC are A(7, 5), B(4, 2), and C(9, 2). What is measure of angle ABC? 30° 45° 56.31° 78.69°

GenaCL600 [577]

The measure of angle ABC is 45°

Explanation

Vertices of the triangle are: A(7, 5), B(4, 2), and C(9, 2)

According to the diagram below....

Length of the side BC (a) $=\sqrt{(4-9)^2+(2-2)^2}= \sqrt{25}= 5$

Length of the side AC (b) $= \sqrt{(7-9)^2 +(5-2)^2}= \sqrt{4+9}=\sqrt{13}$

Length of the side AB (c) $= \sqrt{(7-4)^2 +(5-2)^2} =\sqrt{9+9}=\sqrt{18}$

We need to find ∠ABC or ∠B . So using Cosine rule, we will get...

$cosB= \frac{a^2+c^2-b^2}{2ac} \\ \\ cos B= \frac{(5)^2+(\sqrt{18})^2-(\sqrt{13})^2}{2*5*\sqrt{18} }\\ \\ cosB= \frac{25+18-13}{10\sqrt{18}} =\frac{30}{10\sqrt{18}}=\frac{3}{\sqrt{18}}\\ \\ cosB=\frac{3}{3\sqrt{2}} =\frac{1}{\sqrt{2}}\\ \\ B= cos^-^1(\frac{1}{\sqrt{2}})= 45 degree$