There's many properties you can use to find an unknown angle.
There are too many to lists but one core example would be an isosceles triangle that has two adjacent sides and angles.
Let's say that the sides of an isosceles triangle are any number "x"
now since two sides of the triangle are the same we can add these two x's together.
x+x = 2x
now the other side of the triangle can be anything you like. We can call it 4x for this example.
now if we add them all together we'll get 4x+2x=6x
Now since the angles of a triangle add up to 180 degrees
we can equate 6x=180 leaving x to be 30.
Now since x belongs to both sides of the triangle we can say that both angles are congruent as well because the two sides of the triangle are congruent. This is a known triangle law.
Since both angles are now 30 degrees this will leave us with 2(30) = 60
now if we subtract 180 - 60 we'll get 120 which is the remainder of the 3rd angle of the side that corresponds with 4x.
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Answer: B) 4 & 1/6
Nice work on getting the correct answer.
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Explanation:
x is opposite the marked acute angle
5 is opposite the corresponding acute angle
So x and 5 are proportional to each other. We can form the ratio x/5
Similarly, 10 and 12 are proportional to one another. We can form the ratio 10/12.
Set those ratios equal to each other and solve for x
x/5 = 10/12
12x = 5*10 ... cross multiply
12x = 50
x = 50/12 ...... divide both sides by 12
x = (25*2)/(6*2)
x = 25/6
x = (24+1)/6
x = 24/6 + 1/6
x = 4 + 1/6
x = 4 & 1/6 which shows why <u>choice B</u> is the answer.
Side note: 25/6 = 4.167 approximately
Answer:
A
Step-by-step explanation:
Hi
I think, I'd go with A) Always true. As 2 points is always the line. If you add third one, it will be collinear.
