Answer:
D.) rational numbers are associative under subtraction
Step-by-step explanation:
rational numbers are closed under subtraction
↳ TRUE
zero is the identity for addition of rational numbers
↳ TRUE
subtraction is the inverse of the addition
↳ TRUE
rational numbers are associative under subtraction
↳ FALSE
Answer:
that is really so difficult ? what do you not understand here ? please let me know, if you need any further explanations.
you know what the perimeter is ? if it's the circumference, the way around the object. in other words, the distance you have to walk, when going along all sidelines of the object.
so the perimeter is the sum of of all side lengths.
56 = x - 1 + 3x + 3x + 1 = 7x
x = 8
that gives us the side lengths :
x - 1 = 7 cm
3x = 21 cm
3x + 1 = 22 cm
the formula for the area of a triangle
A = baseline × height / 2
the advantage of a right-angled triangle in this regard is that the sides enclosing the 90 degree angle are already "acting" as baseline and the height (standing on the baseline with a 90 degree angle).
so, we can simply say here, the 3x side is the baseline, and the x-1 side is also the height.
therefore,
A = 21×7/2 = 147/2 = 73.5 cm²
Answer:
Divide each side of 18/4 by 2 to get <u>9/2.</u>
Answer:
14/17
Step-by-step explanation:
Find the value to make the equation true
1) ?/1 = 14/17
x : 1 = 14 : 17
x = 1 * 14 : 17
x = 14 : 17
x = 14/17
Every cm on the map = 8/2 = 4 km
so 16 cm is equivalent to 4*16 = 64 km Answer