R=-7, you have to put each answer in the equation, therefore; 21=42-3(-7) So you have to do multiplication (PEMDAS, if you arent aware of that acronym then it stands for the order of what to do with an equation, Parentheses get solved first, then Exponents, then multiplication, then division, then addition, then finally subtraction. Solving in that order will solve your answer correctly.) With -3 times -7 which gives you 21. Then you do 42 - 21 which equals 21. So 21 = 21.
Quick answer
Any irrational number. I can't think of any exception to this statement.
sqrt(5) is irrational. 1/2 * sqrt(5) is still irrational.
-sqrt(5) is irrational. -1/2 * sqrt(5) is still irrational
2 + sqrt(5) is irrational. Multiplying this by 1/2 is still irrational.
1/2(2 + sqrt(5) = 1 + 1/2 * sqrt(5) ) is irrational.
Conclusion
There are no exceptions to this. All irrational numbers produce irrationals when multiplied by 1/2
Answer:
OB: 4 sides
Step-by-step explanation:
A parallelogram has 4 sides. It is a flat shape with opposite sides parallel and equal in length. Opposite angles are equal.
In the picture below, angles "a" are the same, and angles "b" are the same.
In the case of a parallelogram where all angles are right angles, is a rectangle.
H = -2r + s/πr
C = 3A-a-b
If you need step by step comment