Answer and Step-by-step explanation:

Decreased by 20%
Well the solution to this problem is x < -4
Answer:
1.983(10⁴)
Step-by-step explanation:
Since we need to have ones and decimals as proper scientific notation, we have 1.983. Since we need the value of 19830, we need to move the decimal place 4 places to the right, so our exponent is 4.
*I double checked my work this time.
Answer:
x = 5
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Sum the 3 angles in the triangle and equate to 180, that is
10x - 4 + 8x + 3 + 91 = 180
18x + 90 = 180 ( subtract 90 from both sides )
18x = 90 ( divide both sides by 18 )
x = 5