4/5×1/2= 2/5.
If you want your answer in decimal form than it would be 0.4.
4;81
You subtract 5 from 9 to get 4; 5(9)= 45 9(4)=36 45+39=81
Answer:

Step-by-step explanation:
From the question we are told that:
Generally the equation if differentiated is mathematically given by

Where
y'=0

Factorizing,We have

Therefore
The critical points are

Answer:
C
Step-by-step explanation:
Using the trigonometric identity
csc x = 
Given
sinΘ = - 0.4, then
cscΘ =
= - 2.5 → C
Answer:
19b-4
Step-by-step explanation:
7b+3(4b-2)+6÷3
Bracket comes first so we distribute 3 over the terms in the bracket
= 7b + 12b -6 +6 ÷ 3
First we solve division
= 7b + 12b -6 +6 ÷ 3
= 7b + 12b -6 +2
= (7b+12b)+(-6+2)
= 19b -4
This can't be simplified further as it can't be solved anymore