Answer: the number -5 is a real number
Real numbers are both negative and positive numbers. -5 is a negative number. Since real numbers include negative numbers, -5 is the answer.
Hope this helps!
1.
558 can be rounded to 600.
44 can be rounded to 40.
600 x 40 = 24,000
2.
9 x 802 = 9 (800 +2) =7200 + 18 = 7218
3.
3699 x 7 = (3700-1) x 7 = 25,900 - 7 = 25,893
4.
34 x 93 = 34 x (100-7) = 3400 - 238 = 3162
5.
678 x 87 = 58,986
Its true because scalene doesn't have equal sides