Answer:
Step-by-step explanation:
2{5x²-15+(-9xy²)}-(2y²+4x-xy²)+3x²
=2{5x²-15-9xy²}-(2y²+4x-xy²)+3x²
=10x²-30-18xy²-2y²-4x+xy²+3x²
=13x²-2y²-17xy²-4x-30
Answer:
The probability is
Step-by-step explanation:
From the question we are told that
The number of green marbles is
The number of red marbles is
The number of red marbles is
Generally the total number of marbles is mathematically represented as
Generally total number of marbles that are not red is
=>
=>
The probability of the first ball not being red is mathematically represented as
=>
The probability of the second ball not being red is mathematically represented as
=> (the subtraction is because the marbles where selected without replacement )
=>
The probability that the first two balls is not red is mathematically represented as
=>
=>
The probability of the third ball being red is mathematically represented as
(the subtraction is because the marbles where selected without replacement )
=>
Generally the probability of the first two marble not being red and the third marble being red is mathematically represented as
=>
Answer:
Each interior angle = 135 degrees,
Step-by-step explanation:
The exterior angles of all convex polygons add up to 360 degrees.
So for a regular octagon each exterior angle = 360 / 8
= 45 degrees.
Therefore each interior angle = 180 - 45 = 135 degrees,
Answer: 118
Explanation:
Since ∠A=∠ADB: ∠ADB=61°. The sum of the interior angles of any triangle is 180°, thus:
61°+61°= 122
180-122=58°
∠DBA=58°
Since triangle BCD is an equilateral triangle, all the interior angles are the same:
180/3=60
∠DBC=60°
∠BCD=60°
∠CDB=60°
Since angles DBC and DBA make up angle ABC, just simply add the two angles together:
58+60=118°
Therefore, ∠ABC is 118°.
Answer:
1. rational number
2. a positive rational number
Step-by-step explanation:
A rational number is a number that can be expressed as a simple fraction. When two rational numbers are multiplied together, the only logical answer would be for the outcome/product to also be rational.
The reciprocal of a positive rational number is also a positive rational number because if the original number was negative, the reciprocal would also be negative since the signs wouldn't change (in this case, the original number is positive). Since the original number is already a rational number, just by flipping it (the reciprocal), it would not change to an irrational, but instead stay the same.