Answer:
b=7
Step-by-step explanation:
5a(2b – 3a) = 40
Let a=4
5*4(2b-3*4) = 40
20(2b-12) = 40
Divide each side by 20
20/20 (2b-12) = 40/20
2b-12 =2
Add 12 to each side
2b-12+12 = 2+12
2b = 14
Divide by 2
2b/2 = 14/2
b = 7
Answer:
AB is not a tangent to the circle
Step-by-step explanation:
The angle between a tangent and the radius at the point of contact = 90°
Using Pythagoras' identity to determine if the triangle is right at A
If the square of the longest side is equal to the sum of the squares on the other 2 sides then A is right.
longest side = 15 , then 15² = 225
8² + 9² = 64 + 81 = 145 ≠ 225
Then AB is not a tangent to the circle