It is true due to the commutative property of multiplication. If all of your operations are multiplication, then the integers can move around and you can still get the same answer.
^This is only true if you meant to type (1.8x3)x2.1=(1.8x2.1)x3
If you meant what you typed, then the equation is false. The left side would be 3 times the value of the right side due to the 3 being on the left side and not the right side while without the 3 the two sides would be equal.
Problem 10
<h3>Answer: 80 degrees</h3>
Work Shown: 80-0 = 80
You subtract the values on the protractor where the two angle arms line up.
============================================
Problem 11
<h3>Answer: 45 degrees</h3>
Work Shown: 45-0 = 45
Same idea as problem 10
============================================
Problem 12
<h3>Answer: 83 degrees</h3>
Work Shown: 128-45 = 83
Same idea as the others. The arm TS isn't fully on 130 degrees, and it's a bit short of it. It looks to be about 128 degrees or so.
============================================
Problem 13
<h3>Answer: 35 degrees</h3>
Explanation: Luis forgot to subtract the value of each arm of the angle. So he should have done 80-45 = 35. The answer would be 80 degrees if arm TQ was at 0 degrees (so 80-0 = 80), but instead TQ is at 45 degrees.
Answer:
Step-by-step explanation:
Garden roller is in the shape of cylinder.
So, one revolution = Curved surface area of the cylinder
diameter = 70 cm
radius = 70/2 = 35 cm
h = 100 cm
Curved surface area of the cylinder = 2πrh
= 
= 22000 square cm
Area covered in 15 revolutions = 15 * 22000
= 330000 square cm
2) Coin
diameter = 22 mm
r = 22/2 = 11 mm
Volume of coin = 66 mm
πr²h = 66
