Answer:
9
Step-by-step explanation:
Common ratio = Second term ÷ First term
= 171 ÷ 19 = 9
Answer:
half of 5 is 2.5
2.5 x 3.14 x 2 = 15.7 cm
Formula of circumference:
2(you just always need this number when finding circumference) x pi(3.14 or 22/7 depending on what they tell you to use) x r(radius, half of your diameter or given radius).
<h3>
Answer: AC = sqrt(21)/2</h3>
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Explanation:
Triangle CDA is congruent to triangle CDB. We can use the HL (hypotenuse leg) congruence theorem to prove this. This only works because we have two right triangles.
Since CDA and CDB are congruent, this means their corresponding pieces are the same length. Specifically AD = DB, so
AD+DB = AB
AD+AD = 3
2*AD = 3
AD = 3/2 = 1.5
For triangle CDA, we have AD = 3/2 = 1.5 and CD = sqrt(3). We can use the pythagorean theorem to find the missing side AC
a^2 + b^2 = c^2
(AD)^2 + (CD)^2 = (AC)^2
(3/2)^2 + (sqrt(3))^2 = (AC)^2
9/4 + 3 = (AC)^2
(AC)^2 = 9/4 + 3
(AC)^2 = 9/4 + 12/4
(AC)^2 = 21/4
AC = sqrt(21/4)
AC = sqrt(21)/sqrt(4)
AC = sqrt(21)/2
This is the same as writing (1/2)*sqrt(21) or 0.5*sqrt(21)
Ab means A multiplied by B.
Now, let's say Ab is 1*2
Then ba would be 2*1
So yes, they're technically the same. Just in a different order.
the formula for point slope form is y-y1=m(x-x1)
m is your slope
y1 is your y in the ordered pair
x1 is the x in your ordered pair
example: (5,7) slope is 3
y-7=3(x-5)