3a) Answer: 84 degrees
Step-by-step explanation:
3x + 2(x+20)= 180 (total sum of angles in a triangle is 180 degrees)
5x+40 = 180
5x = 140
x= 28
3x= 28 x 3
= 84
A stop sign shape i think
Answer:
The area of Nancy's garden is 
Step-by-step explanation:
I assume that the Nancy's garden is a rectangle shape
To find the area first convert mixed number to an improper fraction


Therefore
The area is equal to

convert to mixed number

Answer:
The number is 3.
Step-by-step explanation:
To find : A number which decreased by 12 equals 3 times it’s opposite ?
Solution :
Let the number be 'x'.
It's opposite is '-x'.
A number which decreased by 12 equals 3 times it’s opposite
i.e. 
Solving the equation,





Therefore, the number is 3.