Answer:
2r (1 + √3)
Step-by-step explanation:
Circle O₁ is tangent to AB. Let's call the point of intersection point D. If we draw a radius from the center O₁ to D, we know this forms a right angle.
△ABC is an equilateral triangle, so we know m∠A = 60°. If we draw a line from A to O₁, we know that bisects the angle, so m∠DAO₁ = 30°.
So △DAO₁ is a 30-60-90 triangle. We can find the length AD:
AD = r √3
Now on the other side, circle O₃ is tangent to AB. Let's call the point of intersection point E. We know it's the same triangle we found earlier, so:
EB = r √3
And finally, we can draw a rectangle connecting O₁, O₃, E, and D. The distance between O₁ and O₃ is 2r, so:
DE = 2r.
Therefore:
AB = r√3 + 2r + r√3
AB = 2r√3 + 2r
AB = 2r (1 + √3)
Here's a graph showing the steps. Hopefully this helps, let me know if you have questions!
desmos.com/calculator/hgaonfzxsm
I believe you are missing some information here as the answer to the question as it is written is 4.5
Answer:
D. {(2,3) (2,5) (4,7)}
Step-by-step explanation:
2 has an output od 3 and 5, and 4 has an output of 7
Answer:
12. -11
13. 2
Step-by-step explanation:
12. First recall the order of operations (BEDMAS): Brackets, Exponents, Division, Multiplication, Addition, Subtraction
For question 12 there is a division and its priority is before other operations in the equation so you must divide 16/-2 first which gives you -8.
From there because addition and subtraction is on the same level of order, you would do the question straight as it is shown (but replace 16/-2 with -8.
Your new equation is -10-8+7 = -11
13. follow the same as above using BEDMAS. It may help to look at it with additional brackets: ((-68)/(-4)) + ((5 x (-3))
- keep in mind there’s an addition between the two
Division and multiplication is on the same level in BEDMAS so first divide -68/-4 = 17
Second multiply 5 x -3 = -15
Now you can combine the two answers using addition: 17 + (-15) = 2
