Answer:
The value of b is -5
Step-by-step explanation:
Answer:

Step-by-step explanation:
If AB is tangent to the circle, then angle ABO is right angle and triangle AOB is special
triangle. In this triangle, the leg that is opposite to the angle of 30° is half of the hypotenuse. Thus,

By the Pythagorean theorem,

Answer:
7 years
Step-by-step explanation:
Given that:
Let Richard's age = x
Elder sister's age = 2x
Youngwr sister's age = x - 2
Product of sisters ages = 70
2x * (x - 2) = 70
2x² - 4x = 70
2x² - 4x - 70 = 0
x² - 2x - 35 = 0
x² - 7x + 5x - 35 = 0
x(x - 7) +5(x - 7) = 0
(x - 7) or (x + 5) = 0
x = 7 or x = - 5
X can't be negative
Hence, x = 7
Richard is 7 years
Answer: 2/7
Step-by-step explanation: if there are 7 cards and two of them are purple, we can show this as 2/7
Answer: 48x/64
Work (assuming ^ is multiplication):
12x^4/4x^16
12x ^ 4x = 48x
4 ^ 16 = 64